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@dagman input? something a user will enter if you prompt it
Hello! Can anyone help with the Weather App challenge? Cannot get info from my JSON object into my html (I had the same problem with Random Quote Machine and have tried my solution from there with no luck.) Here is my pen: http://codepen.io/lizzieshipton/pen/NNYprM?editors=0010
@Blauelf The API and bot are on different servers.
@Blauelf is this good?
function multiplyAll(arr) {
return arr.reduce(function(a, b) {return a.concat(b)}).reduce(function(a, b) {return a * b});
}
Sure, but the bot could at least feel a little bit depressed if it lost connection.
Add a sad face to the message? :P
its 3:05 a.m. already :worried:
@dagman At least it's pretty unreadable, mission accomplished :P Also, that
arr = is not needed, does not change anything.
@lizzieshipton I think your url is missing a part
need the appid
appid=<yourappid> part i mean
@Blauelf i think for loops works quicklier?
@coymeetsworld i think the appid is included after the +lon, no?
that is the api key that i got from open weather map
no the key is probably fine, but you need to specify that it is the key with appid=X
ahh
ok
like with lon=, lat=, right
@coymeetsworld okay i added that but still nothing is showing on the page. I'm wondering if it's something to do with the function i have written?
whats your url look like?
@dagman Loops are quicker, each function call has some overhead (so for long code blocks the overhead is relatively smaller). I think I would add some standard values, so that it works on empty array, like
return arr.reduce((arr1, arr2)=>arr1.concat(arr2), []).reduce((prod, num) => prod*num, 1);, or use
return [].concat.apply([], arr).reduce((prod, num) => prod*num, 1);
"http://www.api.openweathermap.org/data/2.5/weather?" + "lat=" + position.coords.latitude + "&lon=" + position.coords.longitude + "&APPID=57a5a72171b9dedbcf2ed19869746bbc"
@khaduch hey are you still here?
one sec @lizzieshipton
remove the www?
i also tried that
actually i've taken it out and put it back in a few times lol
// Setup
var myObj = {
gift: "pony",
pet: "kitten",
bed: "sleigh"
};
function checkObj(checkProp) {
// Your Code Here
myObj.hasOwnProperty("checkProp");
return myObj[checkProp];
}
// Test your code by modifying these values
checkObj("house");
how to return "not found" if my object hasn't has the property of hasOwnProperty function
what does position.coords.latitude and position.coords.longitude return? do you get anything from that?
Are you on HTTPS and trying to do a HTTP request?
i actually put that all into a variable string, printed out the variable before i ran it in the call
and tested that in a browser to see if i got a response, maybe try that first to make sure you're getting proper coordinates
@coymeetsworld if i just do the navigator.geolocation part and use .html i can get the position.coords results to show
and also that would verify your appid working
Oh, just added some
http:// in front of the api.openweathermap.org, that one was missing on the codepen...
@coymeetsworld so...stringify (result)? I've actually tried that too and gotten nothing. @Blauelf I've tried it both ways - with http: and without.
no i mean before you call your json function
OMG WAIT
got it
what was the issue?
With http://, it shows some strange string "cmc stations14606787012934246Dusseldorf200"
combination of removing www and adding http (the one combo I hadn't tried yet)
@zico0o Use an if
oh right yeah needs to be http://api.blah
so weird. why is that? why http but not www?
because that is the actual url
a browser will usually fill it in for you
oh so there is actually no www in front of the url
like when you type google.com it really will do the whole thing http://www.google.com
www is just the name of an HTTP server by convention. It has no meaning. The server could have any name, and api.something.tld is the convention for api calls (but not one that strong)
@sludge256 i'm can't get the right condition i tried many things but can't run logically
@coymeetsworld @Blauelf is that something that applies to APIs in general...for example, the open weather map site just says "api.openweathermap.org" and doesn't specify that you need http in front. so all API urls need to have http added to the beginning? (sorry total newb here...)
believe so yes, also had the same problems w/ that
okay cool. man that was driving me crazy lol. thanks @coymeetsworld thanks @Blauelf !
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If you don't specify a protocol (or
// for same-protocol-as-here), your URL is relative path on the same server. Like all those dead links with href="www.google.com". Simply does not work, as this could also be a path on your server (relative to current path), and the browser should not guess.
@zico0o
if object has this property
return the property
else
return a message saying not found
yw @lizzieshipton
:thumbsup: @Blauelf
BTW,
// is not of much help for many free APIs, as they only exist on HTTP.
@zico0o Try posting an attempt at the conditional.
function checkObj(checkProp) {
// Your Code Here
if (myObj.checkProp ===true){
myObj.hasOwnProperty("checkProp");
return myObj[checkProp];
}
else {
return "not Found";
}
} @sludge256
@zico0o
if (myObj.hasOwnProperty(checkProp)) - you want to know whether myObj has a property of the name stored in argument checkProp
i understand it logically but can't get the right syntax yet !!
"checkProp" is not that variable, it's a string.
In addition to @Blauelf 's message, make sure your output messages match the expected results exactly (capitalization, spacing, etc).
i want to know how to return false if hasOwnProperty wasn't fount
Also,
myObj.checkProp is same as myObj["checkProp"], and not what you want. You did it right in the return statement, and that's the only place where you need it anyway.
If you use
hasOwnProperty() inside your conditional it will evaluate to a boolean.
Taking care of your if/else flow.
anyone feel like taking a look at my JS.......i want to run a function using a variable (user input from function before) as an argument.....when i do that it crashes my browser......if i call the function manually entering a number it works fine...i don't understand
thanks @leftynaut for your help with Checkpoint: Record Collection
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at if condition checkProp pass as a variable not string ?? remove quotes ??
'''
var max;
var perc;
var calculatedResult;
var enterWeight;
var enterPercentage;
var plates = [45, 35, 25, 15, 10, 5, 2.5];
function calculateWeight () {
max = document.getElementById('max');
perc = document.getElementById('percentage');
enterWeight = max.value;
enterPercentage = perc.value;
calculatedResult = enterWeight * enterPercentage / 100;
if (document.getElementById('male').checked === true) {
calculatedResult = calculatedResult - 45; } else {
calculatedResult = calculatedResult - 35; }
console.log('enterWeight', enterWeight);
console.log('enterPercentage', enterPercentage);
console.log(calculatedResult);
document.getElementById('result').innerHTML = 'Load Up ' + calculatedResult + ' lbs'
}
var plates = [45, 35, 25, 10, 5, 2.5];
var putThemOn = [0,0,0,0,0,0];
function whatPlates(calculatedResult){
var i = 0;
while (i < plates.length) {
if (2plates[i]<=calculatedResult) {
calculatedResult = calculatedResult - (2plates[i]);
putThemOn[i] += 2;
}
if (2*plates[i]>=calculatedResult) {
i++;
}
}
return putThemOn;
}
console.log(whatPlates(500));
:bulb: to format code use backticks! ``` more info
'''
var max;
var perc;
var calculatedResult;
var enterWeight;
var enterPercentage;
var plates = [45, 35, 25, 15, 10, 5, 2.5];
function calculateWeight () {
max = document.getElementById('max');
perc = document.getElementById('percentage');
enterWeight = max.value;
enterPercentage = perc.value;
calculatedResult = enterWeight * enterPercentage / 100;
if (document.getElementById('male').checked === true) {
calculatedResult = calculatedResult - 45; } else {
calculatedResult = calculatedResult - 35; }
console.log('enterWeight', enterWeight);
console.log('enterPercentage', enterPercentage);
console.log(calculatedResult);
document.getElementById('result').innerHTML = 'Load Up ' + calculatedResult + ' lbs'
}
var plates = [45, 35, 25, 10, 5, 2.5];
var putThemOn = [0,0,0,0,0,0];
function whatPlates(calculatedResult){
var i = 0;
while (i < plates.length) {
if (2plates[i]<=calculatedResult) {
calculatedResult = calculatedResult - (2plates[i]);
putThemOn[i] += 2;
}
if (2*plates[i]>=calculatedResult) {
i++;
}
}
return putThemOn;
}
console.log(whatPlates(500));
:bulb: to format code use backticks! ``` more info
hmmm not sure why the formatting isn't working =(
@camperbot told you, follow that link.
thanks @Blauelf @sludge256
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@zico0o Quotes show that something is a string literal, a value of type string written in javascript code. If you assign that to a variable, you won't start using quotes around that variable name (the meaning of that would be a string that happens to have that variable name inside, but without any connection to the variable).
i can't check for a string in if condition statement i use it as a var without quotes inside my condition.
it run correctly, i was only confused with the right syntax for the condition.
thanks again @Blauelf
it run correctly, i was only confused with the right syntax for the condition.
thanks again @Blauelf
zico0o sends brownie points to @blauelf :sparkles: :thumbsup: :sparkles:
:warning: zico0o already gave blauelf points
@zico0o You don't know that string in advance, so you don't use a string literal, but you get the string as an argument to your function.
@Blauelf since you seem to know what you're talking about :) can you explain truthy to me
Truthy is not falsy. And falsy is any of those six values
0, null, false, undefined, NaN, "". They have in common that truthy values when converted or coerced to boolean become true, and falsy values become false. Most functions that expect a boolean in reality also accept truthy/falsy values. That's how while (arr.length && !func(arr[0])) arr.shift(); works, A&&B evaluates to A if A is falsy, else to B.
anyone feel like taking a look at my JS.......i want to run a function using a variable (user input from function before) as an argument.....when i do that it crashes my browser......if i call the function manually entering a number it works fine...i don't understand
@evanday17 sure just use the correct formatting ~~~js
@evanday17 Show code
let me try that again lol @JSOdin
Backticks, please :)
@evanday17 its ~js <Your code here> ~
@evanday17 "~js your code here ~"
o_o
```js
your code here
```
your code here
```
@Blauelf okay so if I'm checking
collection to see if pre is truthy or falsy on all elements of the array, do I need a giant OR statement such as if collection[i] === 0 || null || ... etc. ?
var max;
var perc;
var calculatedResult;
var enterWeight;
var enterPercentage;
var plates = [45, 35, 25, 15, 10, 5, 2.5];
function calculateWeight () {
max = document.getElementById('max');
perc = document.getElementById('percentage');
enterWeight = max.value;
enterPercentage = perc.value;
calculatedResult = enterWeight * enterPercentage / 100;
if (document.getElementById('male').checked === true) {
calculatedResult = calculatedResult - 45;
} else {
calculatedResult = calculatedResult - 35;
}
console.log('enterWeight', enterWeight);
console.log('enterPercentage', enterPercentage);
console.log(calculatedResult);
document.getElementById('result').innerHTML = 'Load Up ' + calculatedResult + ' lbs'
}
var plates = [45, 35, 25, 10, 5, 2.5];
var putThemOn = [0,0,0,0,0,0];
function whatPlates(calculatedResult){
var i = 0;
while (i < plates.length) {
if (2*plates[i]<=calculatedResult) {
calculatedResult = calculatedResult - (2*plates[i]);
putThemOn[i] += 2;
}
if (2*plates[i]>=calculatedResult) {
i++;
}
}
return putThemOn;
}
console.log(whatPlates(500));
function doubleIt(inpoot) {
var fortyFive = inpoot[0];
var thirtyFive = inpoot[1];
var twentyFive = inpoot[2];
var ten = inpoot[3];
var five = inpoot[4];
var twoPointFive = inpoot[5];
return"Put on " + fortyFive + " 45 lb. plates, " + (fortyFive/2) + " on each side," +
"\n Put on " + thirtyFive + " 35 lb. plates, " + (thirtyFive/2) + " on each side," +
"\n Put on " + twentyFive + " 25 lb. plates, " + (twentyFive/2) + " on each side," +
"\n Put on " + ten + " 10 lb. plates, " + (ten/2) + " on each side," +
"\n Put on " + five + " 5 lb. plates, " + (five/2) + " on each side," +
"\n Put on " + twoPointFive + " 2.5 lb. plates, " + (twoPointFive/2) + " on each side";
}
console.log(doubleIt(putThemOn));var myObj = {
gift: "pony",
pet: "kitten",
bed: "sleigh"
};
function checkObj(checkProp) {
// Your Code Here
if (myObj.hasOwnProperty(checkProp)){
return myObj[checkProp];
}
else
return "Not Found";
}
// Test your code by modifying these values
checkObj("house");
here house is passed at checkObj Arg (checkProp) and also to hasOwnProperty (checkProp) to be checked . but can't check check
checkProp as a string thats what u mean right :D
@Blauelf @JSOdin done
the last code worked :D
@Blauelf
@kmulligan You could
if (collection[i] === 0 || collection[i] === null || collection[i] === false || collection[i] === undefined || collection[i] === "" || collection[i] !== collection[i]) {
console.log("Falsy!")
}or you could simply
if (!collection[i]) {
console.log("Falsy");
}
@evanday17 ok your standalone code works, but youre saying it dont work when you feed the input via a form?
@evanday17 we also need to see your html I believe lol
! will be true for falsy, false for truthy values (that's why !! converts to boolean, negating twice)
@JSOdin console.log(whatPlates(500)); work fine but when i try console.log(whatPlates(calculatedResult)); it crashes.......i want to run the function based off the user input
let me throw it on a codepen
@Blauelf Ok, but I'm not understanding how to test the elements for the second argument. Or am I looking to put
if(!collection[i]) into a function to use array.every(callback)?
@evanday17 gotcha
@Blauelf what about Boolean(value) ?
@Chrono79 That will do about the same as !! (!! is shorter, but Boolean is a function, and for falsy bouncer a function is really useful)
@kmulligan You could use a function like
function(elem) { return pre in elem && elem[pre]; } (if pre is not a key to elem, elem[pre] would silently fail and evaluate to undefined, which is also falsy, so one could skip the first part and just return elem[pre])
having an issue with a for() function....
for(){
for(){
one second
for(){
if(){
}else if(){
}
}
if(){
}else if(){
}
}
problem im having is that the function is returning the values for the final for loop
do i use a break; command to completely exit the for loop?
Too tired to understand that.
lol
@evanday17 ok well I put your js code into an inline script in the html and it works
@evanday17 ithink you referenced your script wrong from the html
is it possible to exit out of a for loop early?
@evanday17 what kind of error u got?
@tylergross Too much guessing the context. Yes, break breaks a loop (unless using labels breaks just one loop), just not sure what you want to achieve.
it just crashes
@evanday17 <script src="BBC.js"></script> <== you need to delete this part, when you type into the JS box on codepen I believe codepen includes that script for you automatically
yeah but i need that for my local file
@Blauelf is that what you meant?
function truthCheck(collection, pre) {
// Is everyone being true?
function hasPre(collection,pre) {
return collection[pre];
}
return collection.every(hasPre);
}
truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy", "sex": "male"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex");
@evanday17 wont work in codepen because codepen looks for BBC.js which doesnt exist
it doesn't work on my local files though,...it just crashes
@evanday17 on your local html file, check if you have the pathing correct
function lookUpProfile(firstName, prop){
// Only change code below this line
var contact = "";
for(var i = 0; i < contacts.length; i++){
if(contacts[i]["firstName"] == firstName){
if(contacts[i][prop]){
return contacts[i][prop];
}else{
return "No such property";
}
}else{
return "No such contact";
} }
// Only change code above this line
}
@evanday17 is your html on the same level of your BBC.js file?
@evanday17 if not, you will have issues
wow that didnt format right
you tried console.log(calcualtedResult)); and it worked?
function lookUpProfile(firstName, prop){
// Only change code below this line
var contact = "";
for(var i = 0; i < contacts.length; i++){
if(contacts[i]["firstName"] == firstName){
if(contacts[i][prop]){
return contacts[i][prop];
}else{
return "No such property";
}
}else{
return "No such contact";
} }
// Only change code above this line
}
@JSOdin not sure i understand what you mean by same level/.
?
@evanday17 same directory level
@kmulligan No.
function truthCheck(collection, pre) {
function truthyPre(elem) {
return elem[pre];
}
return collection.every(truthyPre);
}
@tylergross
help format
:point_right: code formatting [wiki]
Multi line Code
```js ⇦ Type 3 backticks and then press [shift + enter ⏎] (type js or html or css)
<paste your code here>,
then press [shift + enter ⏎]``` ⇦ Type 3 backticks, then press [enter ⏎]
Single line Code
This an inline `<paste code here>` code formatting with a single backtick(`) at start and end around the code.
See also: ☛ How to type Backticks | ☯ Compose Mode | ❄ Gitter Formatting Basics
function lookUpProfile(firstName, prop){
// Only change code below this line
var contact = "";
for(var i = 0; i < contacts.length; i++){
if(contacts[i]["firstName"] == firstName){
if(contacts[i][prop]){
return contacts[i][prop];
}else{
return "No such property";
}
}else{
return "No such contact";
}
}
// Only change code above this line
}
awesome so thats the function but the problem im having is it returns the value of the final check in the for loop
@Blauelf Hmm. Can you explain how
truthyPre can ... use? if that's the right term, use pre even though it wasn't part of the (elem) part?
@tylergross Did that ork for you? I'm on the same one
@tylergross return "No such contact"; should be outside the for
did not work for me, and i'll try that
..just realized @Chrono79 is for Chrono Trigger. Epic.
@tylergross You should use
contacts[i].hasOwnProperty(prop) or prop in contacts[i] to test for property, as a falsy value would trigger the "No such property" path.
@evanday17 i did try console.log(calculatedResult) after I used the form, yes it returns a number.
thanks @Blauelf i'll give that a try
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@kmulligan truthyPre can use all variables declared in outer scopes, for example the arguments to the outer function.
Is this the wrong approach?
function lookUpProfile(firstName, prop){
// Only change code below this line
for (var i=0;i<contacts.length;i++) {
console.log(contacts[i].firstName);
if ( firstName === contacts[i].firstName && contacts[i].hasOwnProperty(prop)) {
return contacts[i][prop];
}
else if ( firstName !== contacts[i][firstName]) {
return "No such contact";
}
else if (!contacts[i].hasOwnProperty(prop)) {
return "No such property";
}
}
// Only change code above this line
}
You should not return "No such contact" before you have tested them all. Return that after your loop.
@Blauelf Oh I see
@Blauelf Ok that makes sense, and you called it
elem since you are testing the elements in collection not the collections in collection?
amazing how misplacement of that "no such contact" return can mess up the entire script. works perfectly now i've been stuck researching this one for a few hours now
@tylergross Can i see what your solution was?
I need something to compare to lol
@kmulligan Yes. Every probably just like filter passes the element, the index, and the array, I just ignore all but the first.
@Blauelf thanks for the explanation
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Hey guys, little theory question for anyone with a bit of JS experience: which of these methods for iterating through an array is considered better?
//https://www.freecodecamp.com/challenges/iterate-through-an-array-with-a-for-loop
function incrementArrayOutput(arr) {
for (var i = 0; i < arr.length; i++) {
console.log(arr[i]);
}
}
// is this 'better'?
function traverseArrayOutput(arr) {
for (var index in arr) {
console.log(arr[index]);
}
}
var arr = [1,2,3];
incrementArrayOutput(arr);
traverseArrayOutput(arr);I ask because to me the one I called 'traverse' seems cleaner, but the FCC lesson teaches the 'increment' method. I was wondering if that was because it was better practice, or just because the increment method works when only accessing odd/even arr elements and they didn;t want to teach both mehods? Any ideas?
Can any one tell me how to complete the Caesars Cipher challenge, how to iterate a given string without using an array.
@JacksonBates with the logic of the incrementArrayOutput for you can iterate no only one by one, you can use the increment you want there, also you can run backwards if you use a decrement, the other way you run through all of the items one by one in ascending order
i need help with this exercise:
One way to think of a multi-dimensional array, is as an array of arrays. When you use brackets to access your array, the first set of bracket refers to the entries in the outer-most array, and each subsequent level of brackets refers to the next level of entries inside.
Example
var arr = [
[1,2,3],
[4,5,6],
[7,8,9],
[[10,11,12], 13, 14]
];
arr[0]; // equals [1,2,3]
arr1; // equals 6
arr[3]0; // equals 11
Instructions
Read from myArray using bracket notation so that myData is equal to 8
@JacksonBates I believe the for... in syntax checks if each item is enumerable so the runtime is longer
encode
hi guys, quick question: Encode the following sequence, separated by spaces:
backslash tab tab carriage-return new-line and assign it to myStr
backslash tab tab carriage-return new-line and assign it to myStr
am i suppose to apply all escaped sequences in there?
yes
@JSOdin you're right - just found this: http://blog.humphd.org/vocamus-1205/?p=1205
My favourite quote from this: "This is one of those things that everyone knows not to do, so they never mention it, and new developers never get told it's bad. Well, it's bad. And it bears repeating." Thanks :)
My favourite quote from this: "This is one of those things that everyone knows not to do, so they never mention it, and new developers never get told it's bad. Well, it's bad. And it bears repeating." Thanks :)
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@JacksonBates np :)
Hello Everyone, I am having a problem with removing spaces from a string.. I tried to do it like this: str = str.replace(/\s/g, ""); but it doesn't seem to work.. What am I doing wrong??
@aGirlWhoCodes err thats the right regex I think
@aGirlWhoCodes let me try
@aGirlWhoCodes Seems right, post the rest of your code.
@aGirlWhoCodes ~~~js
var str = "dog gone good";
console.log(str.replace(/\s/g,''))
~~~
returned "doggonegood" as expected
can anyone help with the testing objects assignment?/??
var str = "dog gone good";
console.log(str.replace(/\s/g,''))@henrywashere
var arr = [
[1,2,3],
[4,5,6],
[7,8,9]]
console.log(arr[0]); // [1, 2, 3]
console.log(arr[0][1]); // 1Does this help?
@cenamorado1 Whats the problem?
how does arry[0] equals [1,2,3]???
GOD THIS IS CONFUSING
Because it's array-ception
this is my code
It's an array or arrays
of*
var myObj = {
gift: "pony",
pet: "kitten",
bed: "sleigh"
};
function checkObj(checkProp) {
// Your Code Here
myObj.hasOwnProperty(checkProp);
return "Not Found";
}
@henrywashere
So an array can have values like this
So an array can have values like this
var array = [1, 2, 3] But instea of numbers it can have another array put inside of it.
I've used an if statement as well and still get it wrong
@cenamorado1 i got two of the tests to pass on that one.
js
<// Setup
var myObj = {
gift: "pony",
pet: "kitten",
bed: "sleigh"
};
function checkObj(checkProp) {
// Your Code Here
myObj.hasOwnProperty("checkProp");
if (true) {
return myObj[checkProp];
}
else {
return "Not Found";
}
}
// Test your code by modifying these values
checkObj("house");
>
yeah I'm if statement was a little like that
still confused
@cenamorado1 ...for some reason the return of "Not Found" isn't woking...
yeah that's what happened to me
@henrywashere Think of an array like a hotwheels car box
it has spaces for each car
@cenamorado1 so the 1st 2 tets passes for u 2?
var array_num = [1, 2, 3]
console.log(array_num[0]); // 1
// Notice we have two sets of brackets here [[]]
var array_array = [[1,2,3]]
console.log(array_array[0]); // [1,2,3]
@cenamorado1 tests*
Array = a box; a box can have other boxes in it. and those boxes can have pencils and erasers
@cenamorado1 In the first example the [0] index was a number, in the second example it was an array
a box within a box within a box wtihin a box within a box within a box
and onwards
oooh ok
@henrywashere @cenamorado1 SOrry got you two mixed up
damnit I thought I had a clue
function palindrome(str) {
str = str.toLowerCase();
str = str.replace(/\s/g, "");
var spaces = str.replace(/[.,\/#!$%\^&\*;:{}=\-_`~()]//,'');
var arr = spaces.split("");
var reversing = arr.reverse();
var end = reversing.join("");
if (str == end) {
return true;
} else {
return false;
}
}
does anyone have working code for the "Testing Objects for Properties" challenge?
@ndburrus Yup, what do you need help with.
@Isymm i posted the code above - the retrurn of false isn't working
@Isymm ...or the return of Not Found
@Isymm 2 of the 3 tests/requirements pass
@ndburrus Your if statement will always return true no matter what you put in there
@Isymm if(true) will always return true.
@ndburrus You need to put a condition in there.
@ndburrus
```js
if (myObj.hasOwnProperty("checkProp");) {
return myObj[checkProp];
}
else {
return "Not Found";
}
```js
if (myObj.hasOwnProperty("checkProp");) {
return myObj[checkProp];
}
else {
return "Not Found";
}
@Isymm right, but what if the value being tested (checkProp) evaluates to false (ie it is not in the key/value pair)
@ndburrus
if (myObj.hasOwnProperty("checkProp");) {
return myObj[checkProp];
}
else {
return "Not Found";
}
@ndburrus Thats what the else statement is for.. If the statement is not true ie it does not have that property. Then it will return not found.
@Isymm my not found else statment looks exactly the same - but something must be different
@Isymm hmmm. u wrapped the check inside the if esle statement
@Isymm thanks... im still not sure why my version didnt work - the logic seems valid
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Hey guys whats the differences in these?
$(elem).on("click", function() {})```$(elem).click()...@ndburrus Sorry for got to remove the quote marks and the semi colon.
if (myObj.hasOwnProperty(checkProp)) {
return myObj[checkProp];
}
else {
return "Not Found";
}Just remember whatever you put inside the brackets of an if statement will be evaluated.
$(elem).on("click", function() {})$(elem).click()...
and elem.onclick()
@ChrisL108
.click is a shortcut for jquery. They do the same thing but .click refers back to .on('click' ...
.click is a shortcut for jquery. They do the same thing but .click refers back to .on('click' ...
ah okay.. what about onclick.. is that the old way to do it?
Pretty sure i saw that used before? other than in HTML
@ChrisL108
elem.onclick is the native API for most browsers it doesnt use jquery its just vanilla js
elem.onclick is the native API for most browsers it doesnt use jquery its just vanilla js
@Isymm alright... :) did u see my code above?
Gotcha @Isymm Thanks for clarifying
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@ChrisL108
Same thing as jquery all of them simply bind event listeners to DOM element. The more you use JS you'll notice there are many different ways of attaching event listeners and handlers to DOM elements. Don't worry about being a bit overwhelemed early on.
Same thing as jquery all of them simply bind event listeners to DOM element. The more you use JS you'll notice there are many different ways of attaching event listeners and handlers to DOM elements. Don't worry about being a bit overwhelemed early on.
@ndburrus yup is it workin?
@evanday17 - kind of here.... I'm pretending to be a cook now... :) Instead of a javascript programmer...
@Isymm the code passed the 1st 2 tests, but not the 3rd (Not Found)
but your request was quite a while ago...
@ndburrus I ran your code, it passing hte first two tests because your if statement will never reach the second condition.
You need to review how if statements work it's what I'm trying to explain to you.
You need to review how if statements work it's what I'm trying to explain to you.
if (true) {
// THIS WILL ALWAYS HAPPEN YOU CAN'T PUT TRUE AS YOUR CONDITION
} else {
// THIS CODE WILL NEVER EXECUTE BECASUE YOUR STATEMENT IS ALWAYS TRUE!
}
@Isymm ok, but i thought the eval ca produce a true OR false
@Isymm can*
Moving into my first week stuck on Diff Two Arrays.
@ndburrus It does, But what you put inside the brackets is the final answer.. the logic is..
if(this statement is true) {
//do this
} else {
// do this.
}
@ndburrus
myObj.hasOwnProperty(myProp) return true or false...
@Isymm ok.
@ndburrus I've shown you how to do it further back, read what I try to understand it as best as possible.
@Isymm i understand ur method. that's what im going with.
@ndburrus Great! tricky stuff this code. :)
@Isymm yep. i think the logic is there for the other way o work, but im at the point of diminishing return on that one
@Isymm to*
@joshbivens yeah - that one stumped me for a little while. The trick for me was to really learn how to use array.filter(). I tried reading the MDN entry for it, but it was a youtube video that finally helped it click for me.
On the Testing Object for Properties lesson, I figured out the answer. // Setup
var myObj = {
gift: "pony",
pet: "kitten",
bed: "sleigh"
};
function checkObj(checkProp) {
// Your Code Here
if (myObj.hasOwnProperty(checkProp) === true) {
return myObj[checkProp];
} else {
return "Not Found";
}
}
// Test your code by modifying these values
checkObj("pet");
But why couldn't you use dot notation for the return like return myObj.checkprop;
why does it have to be bracket notation?
@kevinpschwert you don't need to put the evaluation in there Kevin.. === true. All you need is the myObj.hasOwnProperty(checkProp) that returns you true or false.
@kevinpschwert You have to sue square brackets because obj.checkprop wont lookup the variable it will look for a property called checkprop..
var obj = {
foo : 1,
bar : 2,
checkProp: 'woops'
}
function check(checkProp) {
console.log(obj[checkProp]);
console.log(obj.checkProp);
}
check(foo); // 1 "woops"
@kevinpschwert Actually that example will return woops for both of them but the function illustrates my point. somewhate.
I'm not following what you are saying. Sorry. I think I tried to put what you suggested and I am not getting the correct answer. You are saying that I don't need to us an if else statement?
@kevinpschwert
I was trying to show you why you when you are looking for a property name defined in a variable for example
I was trying to show you why you when you are looking for a property name defined in a variable for example
var checkProp = puppies;
obj[checkProp] //Will look for puppies
obj.checkProp // Will look for a property called checkProp
@Isymm You need to use square brackets when you are working with a variable name rather than the actual name of the property..
My previous example was poorly thought out and will just confuse you. Ignore it.
My previous example was poorly thought out and will just confuse you. Ignore it.
Okay. So dot notation is just for actual name of the property while bracket notation is used for the variable name
Can someone tell me why my jQuery slider lags every time it loops? http://codepen.io/anon/pen/XdEVJQ
@kevinpschwert Essentially yes. Only use dot notation when you know the name of the property you are looking up. Square brackets will look up the value of your variable.
@96street No lag for me
When it goes around the 2nd time most of the container is black @Isymm
@96street Ohh. Okay I get you now.. hmm 1 sec
@96street it's not black for me but I do notice a touch of lag on one picture
Should the Roman Numeral Converter consist of a bunch of
ifs?
@joshbivens There will be a few of them in there. XD
When it goes around after the first time, at one point only the first picture shows @dhcodes
@Isymm Ok good :)
Any idea? @Isymm
@96street on mine all the pictures show, one or two just take longer to load
But I don't think it's a loading error, because I changed all the pictures and they still loaded at the exact same time @dhcodes
only once the first picture goes back to margin-left: 0 (start) then the others appear
@96street Yeah it's not loading the images until it returns to the first slide. You'll need to think of a way to loop so that there is always at least 3 slides shown
That's kind of my question @Isymm
@96street Yeah the way it's designed is obviously to only shown one slide at a time. You'll need to see if there is a way to load images once it reaches the last 3 instead of the last 1.
@96street A quick solution would be to add the first three slides to the end then once it reaches the end -2 postion reset to slide 1.
like this.
hey guys i am really needing help with understanding the "Compound Assignment With Augmented Addition"
Ahh yes good idea. Thanks @Isymm
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Do you know why it only shows one slide at a time in my initial code? @Isymm
@96street Essentially all your code does is scroll past these images. The reason you don't see anything is because once it reaches the last image there is nothing there. However as soon as you are reaching the last slide it resets back to the first position. So if we add the three slides to the end of it then when it scrolls back to the start, we won't notice that a switch has occured.
@Am3ricanPaladin Whats the problem?
Makes sense now (Y)
hey @lsymm I am having trouble understanding the += operator
my assignment looks like this Compound Assignment With Augmented Addition
In programming, it is common to use assignments to modify the contents of a variable. Remember that everything to the right of the equals sign is evaluated first, so we can say:
myVar = myVar + 5;
to add 5 to myVar. Since this is such a common pattern, there are operators which do both a mathematical operation and assignment in one step.
One such operator is the += operator.
myVar += 5; will add 5 to myVar.
Instructions
Convert the assignments for a, b, and c to use the += operator.
code looks like this
var a = 3;
var b = 17;
var c = 12;
// Only modify code below this line
a = a + 12;
b = 9 + b;
c = c + 7;
@Am3ricanPaladin It's a shorthand form so remember that everything on the right hand side of the operator in this case += occurs before the assignment on the left.
right, the computer reads from right to left
@Isymm
var number = 5;
//Long form would be
number = number + 5;
//short form
number += 5;
@Am3ricanPaladin So in that example number is now equal to itself (before the assignment) + 5.
Hello Guys, I need help I'm stuck at "Using Objects for Lookups". What is the syntax of lookup?
@Am3ricanPaladin Instead of creating a whole new variable we have simply reassigned the one we were using before to a new number.
now i dont really understand the "number = number + 5".... basic common sense tells me a number is equal unto itself, a number cannot be plus five of itself... twisting my mind lol
@Am3ricanPaladin SO remember everything on the right hand side happens first.
var number = 5
// new number = old number (5) + 5
number = number + 5;
hmmm
I keep getting
TypeError: Cannot assign to read only property '0' of string 'Hellow World'
My code is
// Setup
var myStr = "Jello World";
// Only change code below this line
myStr = "Hello World";
myStr[0] = "H"; // Fix Me
Oooooh, ok i see thank you @lsymm
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:warning: could not find receiver for lsymm
@Am3ricanPaladin Sorry messed it up before.
Remember we can reassign a variable whenever we want.
Remember we can reassign a variable whenever we want.
var number = 6;
number = 3;
console.log(number) ; // 3
number = number +5;
// is the same as saying make number now equal to 3 + 5.
@Am3ricanPaladin Hope that helps.
@Reapnsow Try this
Ah ha! i got it
myStr = "Hello World"
@r0dJm4n that gives me the same error as before
@Reapnsow Did you remove the
myStr[0] = "H";
@Reapnsow you can't do this myStr[0] = 'H' Strings are immutable meaning they can't be cahnged.. You can't access their indices and change them.
// Setup
var myStr = "Jello World";
// Only change code below this line
myStr[0] = "H"; // Fix Me
@Reapnsow, @Isymm is right you must replace it with new strings
@r0dJm4n that's what i'm supposed to fix
replace
myStr[0] = "H"; with myStr = "Hello World";
@r0dJm4n @Isymm thanks, I guess I misunderstood what the lesson was asking me to do.
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Your welcome @Reapnsow :smile:
// Setup
var collection = {
2548: {
album: "Slippery When Wet",
artist: "Bon Jovi",
tracks: [
"Let It Rock",
"You Give Love a Bad Name"
]
},
2468: {
album: "1999",
artist: "Prince",
tracks: [
"1999",
"Little Red Corvette"
]
},
1245: {
artist: "Robert Palmer",
tracks: [ ]
},
5439: {
album: "ABBA Gold"
}
};
// Keep a copy of the collection for tests
var collectionCopy = JSON.parse(JSON.stringify(collection));
// Only change code below this line
function updateRecords(id, prop, value) {
if (value!=="") {
if (prop!=="tracks") {[id][prop]=value;}
else {tracks.push(value);} }
else {delete [prop];}
return collection;
}
// Alter values below to test your code
updateRecords(5439, "artist", "ABBA");
hey guys can anyone help me out on this
@ALMY91 collection[id][prop]
This message was deleted
Hey, I'm incredibly stuck on Symmetric Difference, could someone offer some pointers? I don't particularly want to look at the answer just yet!
var myMusic = [
{
"artist": "Billy Joel",
"title": "Piano Man",
"release_year": 1973,
"formats": [
"CS",
"8T",
"LP" ],
"gold": true
}
// Add record here
];need help with this:
An easy way to append data to the end of an array is via the push() function.
.push() takes one or more parameter and "pushes" it onto the end of the array.
var arr = [1,2,3];
arr.push(4);
// arr is now [1,2,3,4]
Instructions
Push ["dog", 3] onto the end of the myArray variable.
i wrote ::
arr.push("dog", 3);
didnt work
@jw1540 - there is another challenge "Diff Two Arrays" that does a symmetric difference on just two arrays (I didn't realize that and forgot about it.) I don't know if that will help you with this, at least it's a starting point?
@henrywashere you need to declare a variable called myArray and then push dog and 3 to that
ooooh
@khaduch I'll take a look; thanks bud!
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got it
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@henrywashere :)
thanks @jw1540
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How to create a lookup table?
@tenkdayz
// Setup
var collection = {
2548: {
album: "Slippery When Wet",
artist: "Bon Jovi",
tracks: [
"Let It Rock",
"You Give Love a Bad Name"
]
},
2468: {
album: "1999",
artist: "Prince",
tracks: [
"1999",
"Little Red Corvette"
]
},
1245: {
artist: "Robert Palmer",
tracks: [ ]
},
5439: {
album: "ABBA Gold"
}
};
// Keep a copy of the collection for tests
var collectionCopy = JSON.parse(JSON.stringify(collection));
// Only change code below this line
function updateRecords(id, prop, value) {
if (value!=="") {
if (prop!=="tracks") {collection[id][prop]=value;}
else {collection[id][prop].push([value]);} }
else {delete [prop];}
return collection;
}
// Alter values below to test your code
updateRecords(5439, "artist", "ABBA");
@tenkdayz still not working ..
remove the square brackets from ([value]) @ALMY91
ITS NOT WORKING...i wrote
var myArray = arr.push("dog", 3);
but it wont go through
function nextInLine(arr, item) {
// Your code here
return item; // Change this line
}
// Test Setup
var testArr = [1,2,3,4,5];
// Display Code
console.log("Before: " + JSON.stringify(testArr));
console.log(nextInLine(testArr, 6)); // Modify this line to test
console.log("After: " + JSON.stringify(testArr));
Write a function nextInLine which takes an array (arr) and a number (item) as arguments. Add the number to the end of the array, then remove the first element of array. The nextInLine function should then return the element that was removed.
arr.push(‘dog’, 3) returns the length of the array
i need help with this please
not the array itself
it’s JavaScripts fault not yours
unfortunately that’s just bad language design
so what do i do???
Instructions
Push ["dog", 3] onto the end of the myArray variable.
Push ["dog", 3] onto the end of the myArray variable.
@pmohdameen but i thought to add to the end of an array u have to put [] inside push..
@jackey610 you need to push item then shift array
@henrywashere you do this:
you initialize your myArray variable
var myArray = []
then you push to it
myArray.push(‘dog’, 3)
k lemme try that
@ALMY91 no you dont have to
@tenkdayz i don't know where to start though
or you simply assign it
var myArray = [‘dog’, 3]
like that
:D
@pmohdameen okay but it isn passing through i suppose there is some issue going on my syntax
// Setup
var collection = {
2548: {
album: "Slippery When Wet",
artist: "Bon Jovi",
tracks: [
"Let It Rock",
"You Give Love a Bad Name"
]
},
2468: {
album: "1999",
artist: "Prince",
tracks: [
"1999",
"Little Red Corvette"
]
},
1245: {
artist: "Robert Palmer",
tracks: [ ]
},
5439: {
album: "ABBA Gold"
}
};
// Keep a copy of the collection for tests
var collectionCopy = JSON.parse(JSON.stringify(collection));
// Only change code below this line
function updateRecords(id, prop, value) {
if (value!=="") {
if (prop!=="tracks") {collection[id][prop]=value;}
else {collection[id][prop].push(value);} }
else {delete [prop];}
return collection;
}
// Alter values below to test your code
updateRecords(5439, "artist", "ABBA");
@jackey610 just push item into the given array. then shift that array.. return array.
@ALMY91 yeah
@ALMY91 you have to change your else statement: else {collection[id][prop].push([value]);} }
@henrywashere did you solve it?
i wrote
var myArray = ["dog", 3];
var myArray = ["dog", 3];
didnt go throguh lol
haha! try this
@ALMY91 consider the question : If the prop is "tracks" and value is non-blank, push the value onto the end of the tracks array.
@ALMY91 I think you have to make the first else and else if with prop==tracks
````
var myArray = [];
myArray.push("dog", 3);
var myArray = [];
myArray.push("dog", 3);
@pmohdameen um so shd i include the [] or not?
@ALMY91 no
@ALMY91 you shouldnt include those
didnt work
@ALMY91 and change the syntax as per the question :"If the prop is "tracks" and value is non-blank, push the value onto the end of the tracks array."
The "track" is specified there @ALMY91
gaaaaaaaaaaaaaawd, why is javascript so freakin hard
@henrywashere can i see your code?
var myArray = [];
myArray.push("dog", 3);
myArray.push("dog", 3);
var myArray = [];
myArray.push(["dog", 3]);
@pmohdameen i don think the pb lies w tt
@pmohdameen cause the error msg im getting is After updateRecords(2548, "artist", ""), artist should not be set
@ALMY91 here is it:
change this: collection[id][prop].push(value)
to
collection[id].tracks.push(value);
didnt work either lol
@ALMY91 And please try to understand it :thumbsup:
@henrywashere I just looked at when I did the challenge, I have this:
```
// Setup
var myArray = [["John", 23], ["cat", 2]];
// Only change code below this line.
myArray.push(["dog", 3]);
myArray shouldn't be empty (apologies! i shoulda double checked the challenge for you)
@pmohdameen not working still..
for clarity @henrywashere
// Setup
var myArray = [["John", 23], ["cat", 2]];
// Only change code below this line.
myArray.push(["dog", 3]);
@ALMY91 oh, there is a problem with the delete
@pmohdameen theres nth wrong w the push value tho im passing the criteria for that
YES IT WORKED
:D
thanks @jw1540
:warning: henrywashere already gave jw1540 points
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haha no worries mate, keep at it!
any more help pop me a message, i'd be happy to help :)
awesome, thanks man
@ALMY91 change delete line to : delete collection[id][prop];
@pmohdameen actually it doesn make sense.. if value in arguement is empty it doesn mean that previously that property is empty? so why are we deleting everything in tt property
@ALMY91 please read the question thoroughly
@pmohdameen yeah i read it through alr but isn tt what they are saying. If value is blank, delete that prop.
@pmohdameen so if a value is blank in the arguement but not in the function, we are deleting the whole property off?
@pmohdameen *deleting the whole property off the function
not only from the function but also from the whole record @ALMY91
its a kinda confirmation
var myStorage = {
"car": {
"inside": {
"glove box": "maps",
"passenger seat": "crumbs"
},
"outside": {
"trunk": "jack"
}
}
};
// Only change code below this line
var gloveBoxContents = "myStorage.car.inside[glove box]"; // Change this line
wouldn't gloveBoxContents equal maps???
@pmohdameen okay it just doesn seem practical to me haha..
@pmohdameen but thanks anw
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:) try reading some extra stuffs too
and what about the challenge ? passed ?
@ALMY91 .
@cenamorado1 use ``` before and after your code to format it :)
@pmohdameen passed. i was just thinking if say the user happens to forget adding in the value or smth, then the whole property would be deleted off..
@pmohdameen yep i passed the challenge just that im abit confused with the practicality of this haha
@ALMY91 I think at this point it's just showing how basic functions are done and then as you progress you can look into implementing soft deletes in your applications
by basic functions, i mean crud operations
@jw1540 alright this makes more sense to me haha thanks
@ALMY91 it's good to be thinking ahead about those things, so props for that! i certainly wasn't haha
Hey guys so I'm trying to add to this json object. the instructions are to make a new album and have artist title release year and format properties but the tests are saying it doesn't have any properties, any ideas?
// example code
var myMusic = [
{
"artist": "Billy Joel",
"title": "Piano Man",
"release_year": 1973,
"formats": [
"CS",
"8T",
"LP" ],
"gold": true
}
];
// Add record here
myMusic[1] = [
{
"artist": "Childish Gambino",
"title": "Retro [rough]",
"release_year": 2015,
"formats": [
"CD",
"8T" ],
}
];
@jw1540 hi sir, i sent you a private msg with a problem, can you help me out please?
@shotgunleo format your code by using ``` before and after the code snippet :)
@jackey610 sure bud, not got a private message though?
my bad!
// example code
var myMusic = [
{
"artist": "Billy Joel",
"title": "Piano Man",
"release_year": 1973,
"formats": [
"CS",
"8T",
"LP" ],
"gold": true
}
];
// Add record here
myMusic[1] = [
{
"artist": "Childish Gambino",
"title": "Retro [rough]",
"release_year": 2015,
"formats": [
"CD",
"8T" ],
}
];
@shotgunleo which challenge is it?
@jw1540 introducing javscript object notation json
@shotgunleo - you need to add that new entry within the original array, so just before the closing bracket, you enter a comma after the previous object, and then enter your new one in a similar manner. That is what they are expecting
ah okay I had that before just without a comma so I guess it didn't work, thank you very much!
Hi all, can anyone recommend a library/strategy to parse this type of api response: http://78.31.66.208:8080/urest/doc/6a665314-44ac-4fd9-af73-ed975fb19018 Would http://pegjs.org/ be suitable?
shoudnt this play music?
var audio = new Audio('http://picosong.com/static/widget/index.html?file=/cdn/789b3fc71aa1e16d256e861ef0965fb1.mp3&autoplay=true');
audio.play();@ZctrapCoding
var audio = {};
audio['x'] = new Audio();
audio['x'].src = url;
audio['x'].play()I think that should work..
can any type of statement exists within a switch function?
I'm trying to get the json.forEach loop to work, but I'm having some problems. Is there anyone that can help me with this?
http://codepen.io/GerardJ/pen/RaQPQm
http://codepen.io/GerardJ/pen/RaQPQm
function bouncer(arr) {
var fix = [];
function isTrue(value) {
return value !== false;
}
var newArr = arr.filter(isTrue);
return newArr;
}
bouncer([7, NaN, null, 2, undefined]);[7, null, null, 2, null]
even when I add in things to the
return line like value !== null && value !== ""; it still returns null in place of NaN. Anyone know why?
Hey, in order to convert Celsius to Farenheit, I have the following solution that doesn't work:
Can someone please explain what I'm doing wrong and how to fix it:
function convertToF(celsius) {
// Only change code below this line
var convertToF = 9/5 + 32;
// Only change code above this line
return fahrenheit;
}
// Change the inputs below to test your code
convertToF(30);
convertToF(20);
convertToF(10);
convertToF(0);
convertToF(-10);
convertToF(-20);
@AndrewThM Currently your solution would only be correct if fahrenheit = 0
Sorry celsius
Also you're not returning the variable you created
@AndrewThM your function takes an argument
celsius and returns fahrenheit, but what you've added doesn't use either of those.
I'm trying to create a variable for fahrenheit and apply it to an algorithm to assign it to the corresponding temp in farenheit
@buckshot307 You need to create a variable for fahrenheit. IMHO, it's easier to work with decimals than fractions.
yes the variable is the correct equation, but it doesn't use the input argument
celsius and doesn't return that value as fahrenheit.
@AndrewThM Let's break your function down. You start by taking in celsius as a parameter. Then you define a variable named convertToF which is equal to 9/5 + 32. Finally you return the (undeclared) variable fahrenheit.
There are two things wrong with your function. Try to figure out what they are.
Sorry, I thought it was your code, @buckshot307 . @AndrewThM you need to create a variable for fahrenheit. IMHO, it's easier to work with decimals than fractions.
currently I think I have one thing right: the convertToF(0)
function convertToF(celsius) {
// Only change code below this line
var fahrenheit = (9/5 + 32);
// Only change code above this line
return fahrenheit;
}
// Change the inputs below to test your code
convertToF(30);
@AndrewThM Look at how you define fahrenheit
It's only correct when celsius = 0
@Andrew ThM Your formula, 9/5 + 32 to convert Celsius to Fahrenheit, does not have a place for the Celsius variable. The correct formula is (Celsius * 9/5) + 32.
hey guys, I keep getting "value.toFixed is not a function" error in my console even though I explicitly checked that 'value' is a number with "typeof" the line before. Has anyone had that issue before?
here's the troublesome part of code:
while(change>=0.01 && pennies>0)
{
console.log(change);
ansPennies+=0.01;
console.log(typeof ansPennies);
console.log(ansPennies = " old PENNIES");
ansPennies = ansPennies.toFixed(2);
pennies-=0.01;
change-=0.01;
}
thanks Vivienne. Completed.
hi, I would need some help with Stemroller problem. When I enter the tests manually into the code they give the correct output however they don't pass.
var my_arr = [];
var steamrollArray = function (arr) {
if(typeof(arr) == "object") {
for(var i = 0; i < arr.length; i++) {
steamrollArray(arr[i]);
}
}
else {
my_arr.push(arr);
}
return my_arr;
};
steamrollArray([1, {}, [3, [[4]]]]);Any ideas?
as the task suggests
function multiplyAll(arr) {
var product = 1;
// Only change code below this line
for (var i =0 ; i< arr.length;i++) {
for(var j=0 ; j<arr[i].length; j++)
console.log(arr[i][j]);
}
// Only change code above this line
return product;
}
// Modify values below to test your code
multiplyAll([[1,2],[3,4],[5,6,7]]);
anyone can help me out here..
@ALMY91 shouldnt you multiply the elements ?
@kirbyedy
function multiplyAll(arr) {
var product = 1;
// Only change code below this line
for (var i =0 ; i< arr.length;i++) {
for(var j=0 ; j<arr[i].length; j++)
console.log(arr[i][j]);
product*=arr[i][j];
}
// Only change code above this line
return product;
}
// Modify values below to test your code
multiplyAll([[1,2],[3,4],[5,6,7]]);
@kirbyedy seems like somewhere is wrong..
well console log line and the next line are not the same
@Radascript I think you have to
parse it before calling the the toFixed() method. This method converts a number into a string, so I think the second time around your while loops fails because ansPennies is now a string?
@kirbyedy what do u mean tho
@ALMY91 if you take that line from the console in the brackets and replace it in the next line after *= ?
Please helpy fellas help me with this challange called "Make object properties private"
what will happen
var Bike = function(currentGear) {
// Only change code below this line.
var gear = currentGear;
this.getGear = function() {
return gear;
}
this.setGear = function() {
return gear;
}
};
@ALMY91 you are close
although it should be the same
I am testing it now, and it passes
okay so i made an infinite loop on a challenge and now i can't pull that challenge up without my browser crashing. what do?
@kirbyedy it worked thanks. but im just wondering why it didn work when console.log was present
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@ydeepk check your setGear function. this generally would be to set a value from a parameter passed to the function, and wouldn’t return anything
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@Jlipschitz ahhh that makes sense, so it would work fine the first time and then run into an error. thanks, I'll see if that helps!
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@paulmanning nope nothing happenning
@ydeepk like this….
this.setGear = function(val) {
gear=val;
}
@buckshot307 clear your cookies or open the challenge from another browser
got it. Had to clear browsing data for the past hour lol.
@paulmanning that worked man. Thanks :-)
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@ydeepk Happy to help
@Jlipschitz no, errors even if i parse after or in the same line.
interesting. how are you parsing it?
@Jlipschitz when in one line, like this:
function multiplyAll(arr) {
var product = 1;
// Only change code below this line
for (var i =0 ; i< arr.length;i++) {
for(var j=0 ; j<arr[i].length; j++)
console.log (arr[i][j]);
product*=arr[i][j];
}
// Only change code above this line
return product;
}
// Modify values below to test your code
multiplyAll([[1,2],[3,4],[5,6,7]]); while(change>=0.01 && pennies>0)
{
console.log(change);
ansPennies+=0.01;
console.log(typeof ansPennies);
console.log(ansPennies = " old PENNIES");
ansPennies = parseFloat(ansPennies.toFixed(2));
pennies-=0.01;
change-=0.01;
}
does anybody know why it doesn work when there is a console.log
but it works when i take away the console.log line tho
when in two lines, I just did the same toFixed, then immediately after parseFloat it
```js
function multiplyAll(arr) {
var product = 1;
// Only change code below this line
for (var i =0 ; i< arr.length;i++) {
for(var j=0 ; j<arr[i].length; j++)
console.log (arr[i][j]);
product*=arr[i][j];
}
// Only change code above this line
return product;
}
// Modify values below to test your code
multiplyAll([[1,2],[3,4],[5,6,7]]);
@ALMY91 Try opening up your browser console log and look for errors there. That helps me a lot. Aside from that, perhaps remove the space between the console.log and the ().
@Radascript you're right... hmm. I actually tried
parseFloat(ansPennies).toFixed(2) and it runs but typeof returns string each time. it does increment and decrease though
@paulmanning actually when i take away the console.log line it works
@paulmanning as in the whole line of console.log
@paulmanning taking away the space doesn help tho
@Jlipschitz that's so strange, I wonder what's going on. Mine keeps returning a number but refusing to acknoledge toFixed: http://i.imgur.com/LW2YXyw.jpg
I'll try punching it into codepen or something and see if it's broken there too
@ALMY91 as @paulmanning said there is a NaN logged in the console once you run it, and the freecodecamp test does not let you pass
@kirbyedy so ya mean in a normal setting this would actually work?
dont know
@ALMY91 I tried it in codepen and it has the same issue
@kirbyedy @ALMY91 even when you console.log(product) before returning it
when you comment out his console.log(arr[i][j]) it works fine
if you make it like this it will work:
product*=arr[i][j];
console.log(product);
@kirbyedy is there a reasoning for this?
most probably, but I am not so experienced to explain why, sorry :)
@Radascript
while(change>=0.01 && pennies>0)
{
console.log(change);
parseFloat(ansPennies+=0.01);
console.log(typeof ansPennies);
console.log(ansPennies + " old PENNIES");
ansPennies = parseFloat(ansPennies.toFixed(2));
console.log(ansPennies + " new PENNIES");
pennies-=0.01;
change-=0.01;
}Give this a shot
I'm curious about this issue, because it's concerning to me that console.logging something can actually affect the way your code runs, I would like to know if we need to be more careful about it.
whats the difference between a for loop and a while loop
@Radascript me too but seems like noone here is able to answer the question
@Jlipschitz omg thank you it worked!! You are a breathing gooooooood XD
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:warning: radascript already gave jlipschitz points
@ALMY91 have you attempted any of the lessons?
@ALMY91 Use a for loop when you know exactly how many times you need to iterate. Use a while loop when you cannot be sure in advance how many times you need to loop and must test a condition.
Nicely put @Zerazera
@ALMY91 for loops are good if you need to use the iterator for something. Usually for the index of an array. W while just loops until a condition is not met. you would have to manage the iterator in that loop
yourself
i think
ansPennies+=0.01 at the top was throwing it off for some reason but worked when i forced it to be a float. also you had console.log(ansPennies = " old Pennies) which i switched out to +
@ALMY91 google is not showing me anything either for the consolelog issue. Maybe post on reddit/r/learnprogramming?
@Radascript awesome!!!
@ChrisL108 @Zerazera yeah i have just wanted a summary of it haha
@ChrisL108 Thanks
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@Zerazera thanks
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@Radascript how was console.log affecting the code?
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@Radascript okay good idea.. before i forget all abt it
@ChrisL108 it's in @ALMY91 's code. It runs fine if you comment out his console.log(arr[i][j]) but doesn't work when it's consoling. Here:
function multiplyAll(arr) {
var product = 1;
// Only change code below this line
for (var i =0 ; i< arr.length;i++) {
for(var j=0 ; j<arr[i].length; j++)
console.log(arr[i][j]);
product*=arr[i][j];
}
// Only change code above this line
console.log(product);
return product;
}
// Modify values below to test your code
multiplyAll([[1,2],[3,4],[5,6,7]]);
@Radascript @Radascript there's not { after the second loop
@sonicadept Because the preceding for is not bracketed
@Radascript
Oh yeah they're right
oh yeah @ALMY91 @kirbyedy look, @tenkdayz @Zerazera solved it. whew that was spooky
hello i was doing check for Palindromes in Basic Algorithm, how do i print the value of string2 and string3 in the console, i used
console.log(string2); but it is not working, help me please. here is my code function palindrome(str) {
// Good luck!
var expression = /\W\s/g;
var string1 = str.replace(expression);
var string2 = string1.toLowerCase();
console.log(string2);
var string3 = function reverse(string2){
return string2.split("").reverse().join("");
};
if(string3 === str){
return true;
}
else {
return false;
}
}
palindrome("eye");
@Radascript wait a min what i didn get it lol
@sameershamsudheen underscore
@ALMY91 you didn't put brackets around your second for loop, like this:
function multiplyAll(arr) {
var product = 1;
// Only change code below this line
for (var i =0 ; i< arr.length;i++) {
for(var j=0 ; j<arr[i].length; j++)
{
console.log(arr[i][j]);
product*=arr[i][j];
}
}
// Only change code above this line
console.log(product);
return product;
}
// Modify values below to test your code
multiplyAll([[1,2],[3,4],[5,6,7]]);
add one to the regex pattern
so the code was confused about where to go
function whereAreYou(collection, source) {
// What's in a name?
var arr = [];
var sourceProperties = Object.keys(source);
// Only change code below this line
for(var a = 0;a < collection.length; a++){
for(var b = 0; b < sourceProperties.length; b++ ){
if (collection[a].hasOwnProperty(sourceProperties[b])&&
collection[a].sourceProperties[b] === source.sourceProperties[b]){
arr.push(collection[a]);
}
}
}
// Only change code above this line
return arr;
}
whereAreYou([{ first: "Romeo", last: "Montague" }, { first: "Mercutio", last: null }, { first: "Tybalt", last: "Capulet" }], { last: "Capulet" });
@Radascript alright thanks
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okay so i figured it out. yes, you did need to parse but your console.log was what was giving you the error for improper syntax. so all you actually need to write is
while(change>=0.01 && pennies>0)
{
ansPennies+=0.01
parseFloat(ansPennies.toFixed(2));
pennies-=0.01;
change-=0.01;
}BUT when you had:
console.log(ansPennies = " old PENNIES");
// should be console.log(ansPennies + " old PENNIES");is when you get the error value.toFixed() is not a function. the = operator in there instead of + was the culprit. sorry had to figure this one out, was bugging me lol. @Radascript
@tenkdayz Where to add the underscore
@Jlipschitz omfg this is so silly haha. I think this is my second most embarrassing coding typo that had me breaking my head for hours. tyty
// Setup
var myArray = [];
// Only change code below this line.
var i=0 ;
while(i<5) {myArray.push(i); i++;}
@Radascript i missed it completely as well so no worries. i think a lot of bugs are due to the most simple errors. learned something along the way so glad i could help as well
@sameershamsudheen regex pattern
/[\W_]/
may i know whats the reasoning behind that the code will not work if i did not initialize var i?
// Setup
var myArray = [];
// Only change code below this line.
var i=0 ;
while(i<5) {myArray.push(i); i++;}
@ALMY91 if you don’t declare it, then it doesn’t exist
@ALMY91 if you try to do math on an undefined then it will be NaN
@iAmNawa thanks
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anybody knows why was my issue confirmed then closed on github?
@ALMY91 it was probably a repeat issue, I privat messaged you btw
@ALMY91 Because you were missing the curly brackets.
I didn't notice at first
@iAmNawa did you? i didn receive any tho
@tenkdayz Thank You, so
/[\W_]/g this will include all non alpha numeric characters+ underscore, does this include space.
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@ALMY91 click chat privately and it should show up
@sludge256 whats w the confirmed label tho?
@sameershamsudheen yeas
I confirmed that I could reproduce your issue.
That was before I noticed the coding error though.
@sludge256 but why was it closed after confirmation..
@tenkdayz How do i print the current value of each string to the console, to correct my errors
console.log(value); @sameershamsudheen
@ALMY91 because he saw that it was due to a coding error and not an actual bug for the challenge
@Jlipschitz whats the difference between a coding error and an actual bug
coding error is on your part, bug would be due to the site having a coding error
I did unconfirm the issue.
hello i was doing check for Palindromes in Basic Algorithm, how do i print the value of string2 and string3 in the console, i used
console.log(string2);but it is not working, help me please. here is my code
```
function palindrome(str) {
// Good luck!
var expression = /\W\s/g;
var string1 = str.replace(expression);
var string2 = string1.toLowerCase();
console.log(string2);
var string3 = function reverse(string2){
return string2.split("").reverse().join("");
};
if(string3 === str){
return true;
}
else {
return false;
}
}
palindrome("eye");``` @iAmNawa not working in my code
@ALMY91 yes, coding errors do = bugs but just in terms of this case it's wrong syntax in your code editor and not actual bug on the site. if that helps clarify?
I should've done it before I closed the issue but it doesn't really make a difference.
The issue was in regards to
console.log() causing the error, when in fact, it was your incorrect use of curly braces that was causing the error.
@sameershamsudheen it should work .. i dont see any mistake on the syntax
@tenkdayz I only saw a false printing on the console, not printing any string before that false
@sameershamsudheen what are you replacing the expression with in str?
@sameershamsudheen The FCC output window is not the same thing as your browser console.
what's wrong with this D:
function whereAreYou(collection, source) {
// What's in a name?
var arr = [];
var sourceProperties = Object.keys(source);
// Only change code below this line
for(var a = 0;a < collection.length; a++){
for(var b = 0; b < sourceProperties.length; b++ ){
if (collection[a].hasOwnProperty(sourceProperties[b])&& collection[a][sourceProperties[b]] === source[sourceProperties[b]]){
arr.push(collection[a]);
}
}
}
// Only change code above this line
return arr;
}
whereAreYou([{ first: "Romeo", last: "Montague" }, { first: "Mercutio", last: null }, { first: "Tybalt", last: "Capulet" }], { last: "Capulet" });
@trip16661 in your code even if one property-value pair matches, u r pushing that collection into the array.. i dont think that is desired
@rujool i don't know :smile: i was trying to replace the non alpha numeric characters and underscore from the given string.
var string1 = str.replace(expression); is this wrong
don't you need two arguments in "replace"?
var myStr="\"I am a \"double quoted\" string inside \"double quotes\"\" "; //
error
@sameershamsudheen but with what are you trying to replace them?
@Radascript exactly
why still showing errors?
@GitH7 u have extra escaped quotes
Anyone can tell me how to solve Golf code JavaScript basics...
//Setup
var contacts = [
{
"firstName": "Akira",
"lastName": "Laine",
"number": "0543236543",
"likes": ["Pizza", "Coding", "Brownie Points"]
},
{
"firstName": "Harry",
"lastName": "Potter",
"number": "0994372684",
"likes": ["Hogwarts", "Magic", "Hagrid"]
},
{
"firstName": "Sherlock",
"lastName": "Holmes",
"number": "0487345643",
"likes": ["Intriguing Cases", "Violin"]
},
{
"firstName": "Kristian",
"lastName": "Vos",
"number": "unknown",
"likes": ["Javascript", "Gaming", "Foxes"]
}
];
function lookUpProfile(firstName, prop){
// Only change code below this line
if(firstName===contacts[firstName]) {
if(prop===[firstName].hasownprop) {return contacts[prop];}
else {return "No such property";}}
else {return "No such contact";}
// Only change code above this line
}
// Change these values to test your function
lookUpProfile("Akira", "likes");
whats wrong guys
@dhananjaydeath just a hint: use if-elseif
@ALMY91 check the syntax.. if(prop===[firstName].hasownprop)
That i understand but do i need to use these as conditions 1 "Hole-in-one!"
<= par - 2 "Eagle"
par - 1 "Birdie"
par "Par"
par + 1 "Bogey"
par + 2 "Double Bogey"
= par + 3 "Go Home!"
@dhananjaydeath exactly
thanks..
@ALMY91 also contacts is an array of objects
think about that
@rujool solved
@GitH7 gr8
@rujool Is this correct
var string1 = str.replace(expression, '');
@sameershamsudheen yep
Remove all the backslashes ()
You should have two single quotes ' and four double quotes "
Only remove the backslashes \ used to escape quotes.
You should have two single quotes ' and four double quotes "
Only remove the backslashes \ used to escape quotes.
what is 1st and 3rd?
@rujool what about this
var string3 = string2.split('').reverse().join(''); right or wrong
@rujool Remove all the backslashes ()
You should have two single quotes ' and four double quotes "
Only remove the backslashes \ used to escape quotes.
You should have two single quotes ' and four double quotes "
Only remove the backslashes \ used to escape quotes.
var myStr = 'a href="http://www.example.com" target="_blank">Link</a>';
function printAlert() {
for (var i = 0; i < winCombs.length; i++) {
var str = winCombs[i].toString();
var regex = new RegExp(',', 'g');
//replace via regex
str = str.replace(regex, '');
for (var j = 0; j < output.length; j++) {
var testit = output[j].toString();
testit = testit.replace(regex, '');
if (str == testit) {
alert("Computer Won. The evil electric power!");
setTimeout(function() { location.reload(true) }, 4000);
} else if (arrComp.length === 5){
alert("Draw! You are good believe me.");
setTimeout(function() { location.reload(true) }, 4000);
}
}
}
}
why in this code, setTimeout runs before alert?
can anyone tell me?
challange split strings with split
var string = "Split me into an array";
var array = [];
// Only change code below this line.
array = string.split("\s");
what I'm dooing wrong?
what are you trying to do with "\s" ?
@ydeepk
@shivamarora13 spliting array of strings at white space that the challange
just use array.split(' ');
it will split.
@ydeepk
don't forget to give a space between the quotes
split() is a string function, not an array function
@shivamarora13 already tried not working.
@shivamarora13 do you have that on codepen? can't test out of context
@Zerazera look at split strings with split challange
@ydeepk you're using regex without the regex syntax
@ydeepk send the challeng link
@BKinahan you are right.
@ydeepk
split(/\s/)
@BKinahan what should i DO.
@BKinahan it worked man. Thanks Pal. :-)
:star: 1296 | @bkinahan | http://www.freecodecamp.com/bkinahan
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hello
var string1 = str.replace(/\W*\s+/g, '');do this code remove all non-alphanumeric characters and all spaces from the string str
@shivamarora13 found out. @BKinahan helped.
@shivamarora13 http://codepen.io/shivamarora_/full/bpLOPJ/
@BKinahan
this is the link to the pen, can u see why even the alert is not working
@sameershamsudheen spaces are non-alphanumeric already :)
@shivamarora13 the alert works for me. in fact it works too well, it won't stop :P
@shivamarora13 maybe you clicked an option in your browser to prevent it from showing any more alerts?
@BKinahan ok, but my Check for Palindromes challenge still getting 5 more errors, I dont know which part of my code is not working, Here is my code
function palindrome(str) {
// Good luck!
var string1 = str.replace(/\W*/g, '');
var string2 = string1.toLowerCase();
var string3 = string2.split('').reverse().join('');
if(string3 === str){
return true;
}
else {
return false;
}
}
palindrome("eye");
@BKinahan Ohh yess!
ok please tell me, how to make page reload
@BKinahan
after user clicks ok on alert
@shivamarora13 It might be better to re-initialize the game instead of reloading
@shivamarora13 actually I think it does that already; it worked when I tsopped the page from showing any more alerts
@BKinahan and how can I stop alerts, from alerting user infinite times
consider using some way to show text without using
alert, since some people find those annoying :)
@BKinahan Ok, thanks for the advice
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@sameershamsudheen in regex,
* means "match between zero and unlimited times", so \W* might not work very well
@sameershamsudheen you could do
/\W/g instead, but that still doesn't account for the underscore character _ so you will have to consider that too
@BKinahan ok corrected to this
var string1 = str.replace(/\W\_/g, ''); any other errors
@sameershamsudheen no need to escape
_ because it's not a special character. your regex matches an underscore after a non-word character, so you need or in between them using | Test regex here: https://regex101.com/
why isnt this working ?
function fearNotLetter(str) {
var newArr = str.split("");
if (newArr[0] !== "a") {
return undefined;
}
for (i=0;i<newArr.length;i++) {
if (newArr[i].charCodeAt() < newArr[i+1].charCodeAt());
{ return newArr[i];
}
}
}
what is the challenge @EldarT90 and what are you having trouble w/?
@coymeetsworld the if statements is always true, even when i change the sign; how is that possible?
@coymeetsworld challenge is to find letter that is not "following order", for example if we have string (that i turn into array) of a,b,c,d,e,g ... the mistake is e
@coymeetsworld and we should return f; but that can be easy with code+1; however problem is in statement
@coymeetsworld its not working
which sign are you talking about?
@coymeetsworld ascii code, but i see it wont work like this, however i cant google alternative way of getting signs asccii code
so for example you want to get code for sign F
how would you do it
you know that its incremental, A is 65, B is 66, C is 67, etc
so each letter should only be one less than the next one
if it isn't, you know theres a missing character
@coymeetsworld yes, but thats not my problem, probelm is to get code of any letter, regardless of funciton
what is the method to get code of X or Y or A or 9
regardless of any funciton
just to get code, the method
X.chatCodeAt(); wont work
what is X? If you mean letter X you need to encapsulate in quotes
"X".charCodeAt(); would return the character code
yes
but no code
no string*
is it possible to do it without the strig
letter, symbol, number anything but that is not "stringified"
is there method to get its code ?
charCodeAt is a String function, so no
any alternative function ?
has to be a string
you don't need one
well my if statement wont work because array elements are not strings
i think
hmm they should be
actually yes they are after i split it into string
so why wont it work
newArr[i].charCodeAt() > newArr[i+1].charCodeAt())
why is this always ture ?
true*
newArr[i].charCodeAt() > newArr[i+1].charCodeAt()) = true
newArr[i].charCodeAt() < newArr[i+1].charCodeAt()) = true
whichever sign i put, it reads as true
or not
but probleme is in that statement
@EldarT90 check the charCodeAt syntax
@rujool string.chatCodeAt()
you sure it does? that shouldn't make sense
newArr[i] = string
newArr[0] = "a"
the function is fine @rujool
@EldarT90 It is String.charCodeAt(index): https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/charCodeAt
although you don't need to put the string into an array @EldarT90
@rujool if you don't specify an index it defaults to 0
so if he runs that on a 1 character string its fine, which is what he's doing
why am i getting error cannot read property charAt
oh @EldarT90
you have a semicolon at the end of your function
i mean if statement, remove it
yes, but still wont work : i get error cannot read property
function fearNotLetter(str) {
var newArr = str.split("");
if (newArr[0] !== "a") {
return undefined;
}
for (i=0;i<newArr.length;i++) {
if (newArr[i].charCodeAt() > newArr[i+1].charCodeAt())
{ return newArr[i];}
}
}
str.charCodeAt(i) this should go through the string
@EldarT90
@tenkdayz no its ok
the way he's writing it should be fine, its something else
error is : cannot read property charcodeat of undefined
think you may need to specify i<newArr.length-1 @EldarT90
agree @tenkdayz
theres one problem
aa
sec
also you need to define i
i fixed it i think
var i = 0;
function fearNotLetter(str) {
var newArr = str.split("");
if (newArr[0] !== "a") {
return undefined;
}
for (i=0;i<newArr.length;i++) {
if (newArr[i].charCodeAt() !== (newArr[i+1].charCodeAt()+1))
{ return newArr[i];}
}
}
now its working, ofc its not giving me right result yet
but the statement works
This message was deleted
guys hes fine :)
still there is a mistake somewhere there
@EldarT90 think you need to add +1 to newArr[i].charCodeAt(), not newArr[i+1].charCodeAt()
"A" + 1 would be "B"
not
"B" + 1 = "A"
not
"B" + 1 = "A"
yep
sec
right
brainfart i guess
because i was making +2
instead of 0 difference
so now i need to get charcode of that element which is troublesome, add +1
and get letter behind that code
hmm
is there anyone who did algorithm "Map the derbis" ???
*debris
function fearNotLetter(str) {
var newArr = str.split("");
if (newArr[0] !== "a") {
return undefined;
}
for (var i=0;i<newArr.length;i++) {
if (newArr[i].charCodeAt() +1 !== (newArr[i+1].charCodeAt()))
{ var getting = newArr[i].charCodeAt()+1;
return getting;}
}
}
now im getting unicode of the troublesome letter
need to revert function to letter of the code
String.fromCharCode() is your friend.
aa
yep @Blauelf
thats the last part missing
yeaaa
need to convert that ascii value getting to a String of one char
@coymeetsworld @Blauelf ty both of you
it worked!
np @EldarT90 good job
im glad that i stick to my way of solving, even if its not the most efficient, at least i try to solve the problem hehe
Also, that
if (newArr[0] !== "a") looks like you are hard-coding test cases... (remove that line, you already return undefined if you don't explicitly return from your function)
yeah also you don't need to make an array of characters either
you can use str.charCodeAt(index)
but when you specify no index it defaults to 0
@Blauelf they are wanting for undefined to popup if string starts from something weird, which is basically anything but a ? that is how i got the point, i might be wrong ofc
but since you're running them on one character strings thats fine
@coymeetsworld but how can you target "problematic" letter with charcodeat ?
i mean without making it aray
array*
what can i do so i go though every property cheking them before sending it to the new array?
This message was deleted
@EldarT90 One does not need special test, just wait if your loop returns, if not, then return
undefined, for example by not using return after that loop :P
function whereAreYou(collection, source) {
// What's in a name?
var arr = [];
var sourceProperties = Object.keys(source);
// Only change code below this line
for(var a = 0;a < collection.length; a++){
for(var b = 0; b < sourceProperties.length; b++ ){
if (collection[a].hasOwnProperty(sourceProperties[b])&& collection[a][sourceProperties[b]] === source[sourceProperties[b]]){
arr.push(collection[a]);
}
}
}
// Only change code above this line
return arr;
}
whereAreYou([{ first: "Romeo", last: "Montague" }, { first: "Mercutio", last: null }, { first: "Tybalt", last: "Capulet" }], { last: "Capulet" });
something like
for (var i = 0; i < str.length -1; i++) {
if (str.charCodeAt(i)+1 != str.charCodeAt(i+1)) {
return str[i];
}
}
@Blauelf so if there is no return, it counts as undefined ? didnt know that
let me retry
@trip16661 Don't push in your inner loop, push in the outer loop, and only if all things in inner loop matched.
@Blauelf its not working hmm, because it start counting as bcd is correct string
@EldarT90
return; or an implicit return by reaching the function end both count as return undefined;
@coymeetsworld lolz that looks so simple and correct
yeah don't know if that works 100% but thats the general idea, have to go look back at my code to see what I did exactly
@coymeetsworld but yeah, problem is i dont get in my head that this function is special because you can map element INSIDE the string - i mean you can target it
usually we dont work that way
because not too many functions can do that
@EldarT90 Maybe if you try
str.charCodeAt(i) instead of newArr[i].charCodeAt(), and check whether str.charCodeAt(i)+1 !== str.charCodeAt(i+1)?
yeah i see what you mean @EldarT90
@coymeetsworld You would need to use
String.fromCharCode, as it is the missing character you need to return, but other than that, yes, code looks fine :)
right @Blauelf
just wrote something quick up :)
@Blauelf yea, just as @coymeetsworld said, but i need experience for me to intuitively use different fucntion in different way; i am still getting often into for and if mess
which can be evaded mostly
Does anyone know if I can pass a function straight in to
navigator.geolocation.getCurrentPosition( examplefunc (pos));because I cant get it to work ?
I have had to use an anon func to call it ?
navigator.geolocation.getCurrentPosition( function(pos) { examplefunc(pos) });
You can use
function examplefunc(pos) {
// your code
}
navigator.geolocation.getCurrentPosition(examplefunc);
You pass that function a callback function, bu you don't call it yourself. A function (function literal, named function, or variable pointing to function) followed by parentheses means that you call it at the time that code is evaluated. You want to call your callback only after the async action has finished.
So example func without the () ? Thanks @Blauelf
naassi sends brownie points to @blauelf :sparkles: :thumbsup: :sparkles:
:star: 1645 | @blauelf | http://www.freecodecamp.com/blauelf
Hey everyone! I was working on a webapp and having some problem in speech recognition in the videos. Can you tell me which api and framework I use to achieve this..
is there anyone who did the algorithm Map the debris ?
@omiq17 I did that one
function orbitalPeriod(arr) {
var GM = 398600.4418;
var earthRadius = 6367.4447;
var pi = 3.1416;
var mul = Math.sqrt( earthRadius + Math.pow(arr[0].avgAlt,3)/GM );
var ans = 2*pi*mul;
return Math.round(ans);
}
where is the problem in my code? @Zerazera
@omiq This isn't the problem, but you can use Math.PI instead of setting the variable
@omiq17 Include the
earthRadius + in the Math.pow, it adds to avgAlt.
ok... let me try
Not sure how that structure really worked (have to look it up)
@Blauelf Thats not working for me heres the code
if(navigator.geolocation) { navigator.geolocation.getCurrentPosition(getWeather);
} else {
alert("Could not access location;");
};
var getWeather = function(pos) {
$.get('http://api.openweathermap.org/data/2.5/weather?lat=' + pos.coords.latitude +
'&lon=' + pos.coords.longitude + '&units=metric&APPID=f4bb493881267d09c5847a375103e72', function(data) {
$('.location').text(data.name);
$('.description').text(data.weather[0].description);
$('.temp').text(Math.round(data.main.temp) + "°C");
console.log(data);
});
}
I don't think anyone would unless they were a scientist
function factorialize(num) {
var counter = 1;
while(num >= counter) {
num *= (num-1);
counter++;
}
return num;
}
factorialize(5);
what i
'm doing wrong
??
'm doing wrong
??
you're not decrementing num
oh wait you don't need to do that
@ydeepk Google recursion but dont look at examples
*= isn't going to work how you expect
he doesn't need recursion @naassi
num is equal to 5, so num *= (num-1) is going to be 20
then you're going to be running 20 *= 19
Right, factorials can be solved with or without recursion. Recursion is just a bit neater.
@ydeepk Here's a hint: you don't need the counter variable
You can define the while loop in terms of num
yeah but recursion is less efficient with things you can do with a for loop
@Zerazera okkaaaay.. let me try that
@Zerazera Yea it helps to understand it a bit, especially for challenges like that one
@Zerazera nope not working.
@ydeepk What's the code that isn't working
@Zerazera function factorialize(num) {
while(num >= 1) {
num *= (num-1);
num--;
}
return num;
}
factorialize(5);
@ydeepk Think about what happens if num = 5. What will its value be when the loop runs the second time?
@ydeepk you're going to want to create a new variable to store the results in
@ydeepk the problem is that u are assigning num = num*(num-1) but you lose that value when u decrement num
@naassi At the time you call the position, the callback function does not exist. That's a classical use-before-initialize. Note that named function are done first, but assignments of functions are not.
@rujool yea u r right.
@ydeepk as @coymeetsworld said u should create another variable
thanks @Blauelf your suggestion has worked perfectly for me...
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Hello! I'm stuck with "Profile Lookup" task. How can I paste my code here?
@omiq17 I just looked up map-the-debris, and the "map" in the title might be a hint. You are meant to map objects to other objects (then no longer with avgAlt, but with orbitalPeriod), so return an array with the same number of objects as the input array.
help format
:point_right: code formatting [wiki]
Multi line Code
```js ⇦ Type 3 backticks and then press [shift + enter ⏎] (type js or html or css)
<paste your code here>,
then press [shift + enter ⏎]``` ⇦ Type 3 backticks, then press [enter ⏎]
Single line Code
This an inline `<paste code here>` code formatting with a single backtick(`) at start and end around the code.
See also: ☛ How to type Backticks | ☯ Compose Mode | ❄ Gitter Formatting Basics
@broc93 :point_up:
thank you @negyvenketto
broc93 sends brownie points to @negyvenketto :sparkles: :thumbsup: :sparkles:
:star: 365 | @negyvenketto | http://www.freecodecamp.com/negyvenketto
function lookUpProfile(firstName, prop){
var f = false;
var p = false;
for (var i = 0; i<contacts.length; i++){
if (contacts[i].firstName==firstName){
f = true;
if (contacts[i][prop]===""){
return "No such property";
} else return contacts[i][prop];
}
}
if (!f) return "No such contact";
}
i did that using a for loop & my challenge has completed... :smile:
@Blauelf
@broc93 Use hasOwnProperty ;) Also, no need for any f or p (return instantly leaves the function, returning whatever you specified as a return value)
function switchOfStuff(val) {
var answer = "";
// Only change code below this line
switch (val) {
case a:
answer = "apple";
break;
case b:
answer = "bird";
break;
case c:
answer = "cat";
break;
default:
answer = "stuff";
}
// Only change code above this line
return answer;
}
// Change this value to test
switchOfStuff(c);
why am i geting reference error here?
c is not defined
@omiq17 As map is just a hidden loop, that's about the same.
@Jaromirx
"a" (string literal of letter a), not a (variable of name a)
i tried with "" ...same error
Around a, b, and c each?
yea
Also in
switchOfStuff(c)?
yep
So on every occurence (those are 4 in your code, one a, one b, two c) at the same time?
@Blauelf thank you!!!
broc93 sends brownie points to @blauelf :sparkles: :thumbsup: :sparkles:
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@Jaromirx shouldnt you have the break even after the default
Hi, I am working on the Intermediate Algorithm Scripting assignment that is about summing all primate numbers up to a given number. Here's the code:
function sumPrimes(num) {
//checks if a number is a prime, works correctly
function checkIfPrime(n) {
for (i = 2; i < n; i++) {
if (n % i === 0) {
return false;
} else if (i + 1 == n){
return true;
}
}
}
var primes = [];
for (j = 2; j <= num; j++) {
console.log('j = ' + j + ', num = ' + num); //logs correctly for each loop
if (checkIfPrime(num)) { /in this loop nothing gets executed
console.log(j);
primes = primes.push(num);
console.log(primes);
}
}
console.log('Im here');
/*
primes.reduce(function(previousVal, currentVal) {
return previousVal + currentVal;
});
*/
}
sumPrimes(10);Could someone please help? I'm tottaly stuck. I have no idea why the for loop does not get executed (why the condition is never passed)
@kirbyedy no need for that
ok
not javascript related, can I post it?
nah ...dunno why this isnt working its buging me ..whatever i write in that switchOfStuff(x) ... i get ReferenceError: x is not defined
@Jaromirx can you paste your code again with corrections @Blauelf told you
@mtmorawska have you tested your checkIfPrime function? does it work?
@Jaromirx That's why I asked if you added "" also around that c. Does it work on
switchOfStuff("x")?
@mtmorawska There is only one slash on your comment
/in this loop nothing gets executed
function switchOfStuff(val) {
var answer = "";
// Only change code below this line
function switchOfStuff(val) {
var answer = "";
// Only change code below this line
switch (val) {
case "a":
answer = "apple";
break;
case "b":
answer = "bird";
break;
case "c":
answer = "cat";
break;
default:
answer = "stuff";
}
// Only change code above this line
return answer;
}
// Only change code above this line
return answer;
}
// Change this value to test
switchOfStuff("a");
@Blauelf you are online all the time?
ok i got 2xreturn answer there ignore that :D
@Jaromirx use code format
@mtmorawska You should declare variables using
And your checkIfPrime won't consider 2 prime, better use a
var (might prevent some surprises, as undeclared variables might be global if not declared in some scope between).And your checkIfPrime won't consider 2 prime, better use a
return true; outside your loop instead of inside.
how do i use code format?
@negyvenketto yes, I did
to post code
help code format
:point_right: code formatting [wiki]
Multi line Code
```js ⇦ Type 3 backticks and then press [shift + enter ⏎] (type js or html or css)
<paste your code here>,
then press [shift + enter ⏎]``` ⇦ Type 3 backticks, then press [enter ⏎]
Single line Code
This an inline `<paste code here>` code formatting with a single backtick(`) at start and end around the code.
See also: ☛ How to type Backticks | ☯ Compose Mode | ❄ Gitter Formatting Basics
Hi wanted some help with parsing JSON. I have used stringify to get the raw data display but don't know who to only get selected items (e.g. game or status null). This is for Twitch TV and codepen is http://codepen.io/vaspv/pen/VaXLyG
@Jaromirx Function in function? Bad copy&paste?
yeah bad copy paste
anywayz i reseted and pasted same stuff again and it worked
some king of bug i guess
@vaspv have you tried... if stream is null, offline otherwise online
@Blauelf how can I
return true outside of the loop?
but you will also have to check for closed accounts
@mtmorawska
function checkIfPrime(n) {
for (i = 2; i < n; i++) {
if (n % i === 0) {
return false;
}
}
return true;
}
@kirbyedy hi yes that is what I want to ultimately achieve but how do I find out if stream value is null? if I type data.stream === null or data[0]=== null then nothing is fetched . This is where I'm stuck - on how to get the value of a specific field only like stream or game or id etc.
@negyvenketto Thanks :) (I would recommend adding a
var in front of i for not making a global variable)
@Blauelf yes, you are right, i forgot that. i tend to edit code and forget to fix half of the things...
@negyvenketto Ok, thanks. That still doesn't solve the problem though.
mtmorawska sends brownie points to @negyvenketto :sparkles: :thumbsup: :sparkles:
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@mtmorawska i found your other problem
@mtmorawska in the loop you want to check if j is a prime, not num
@mtmorawska and you want to push that
@negyvenketto that must be it!
@mtmorawska also, you might want to review how the push function works
How can I get into match variable matched value?
function replacer(match) {
return match; // got '$&'
}
"&<>'".replace(/[&<>"']/gi, replacer('$&') );// got "&<>'"
//but
"&<>'".replace(/[&<>"']/gi, '$&'); // got "&<>'"
@negyvenketto I'll check that, and let you know how it went. Thanks so much for your input!
mtmorawska sends brownie points to @negyvenketto :sparkles: :thumbsup: :sparkles:
:warning: mtmorawska already gave negyvenketto points
@mtmorawska yw
@vaspv it should be data.stream
@cvdeby
"&<>'".replace(/[&<>"']/gi, replacer) like this? replacer will be called with a couple of arguments, but the first is the whole match (followed by groups, then I think some start index and the whole string, but that's in the documentation of replace
@Blauelf Thanks)
cvdeby sends brownie points to @blauelf :sparkles: :thumbsup: :sparkles:
:star: 1648 | @blauelf | http://www.freecodecamp.com/blauelf
@negyvenketto it worked!
@mtmorawska :thumbsup:
Thanks to @Chrono79 for dictionary)
var dictionary = {
'&' : '&',
'<' : '<',
'>' : '>',
'"' : '"',
"'" : '''
};
function replacer(match) {
return dictionary[match];
}
function convertHTML(str) { return str.replace(/[&<>"']/gi, replacer );
}Can I make it directly -without dictionary?
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@cvdeby probably yes, but it wont be so clean/easy to understand
var contacts = [
{
"firstName": "Akira",
"lastName": "Laine",
"number": "0543236543",
"likes": ["Pizza", "Coding", "Brownie Points"]
},
{
"firstName": "Harry",
"lastName": "Potter",
"number": "0994372684",
"likes": ["Hogwarts", "Magic", "Hagrid"]
},
{
"firstName": "Sherlock",
"lastName": "Holmes",
"number": "0487345643",
"likes": ["Intriguing Cases", "Violin"]
},
{
"firstName": "Kristian",
"lastName": "Vos",
"number": "unknown",
"likes": ["Javascript", "Gaming", "Foxes"]
}
];
function lookUpProfile(firstName, prop){
// Only change code below this line
for (var i=0;i< contacts[i].length ; i++)
if(firstName===contacts[i][firstName]) {
if(prop===contacts[i][firstName].hasownprop(prop)) {return contacts[i][prop];}
else {return "No such property";} }
else {return "No such contact";}
// Only change code above this line
}
// Change these values to test your function
lookUpProfile("Akira", "likes");
whats going on guys
@negyvenketto I'll use
& instead, if it'll be needed in real project)
@ALMY91 hasOwnProperty
you can't use functions with all lowercase
The name is hasOwnProperty (and has to be written like that, that function returns true or false)
Also, use
contacts[i].firstName or contacts[i]["firstName"] (as firstName is not a property name but the value to compare to, but "firstName" is the name)
And fix the indentation (it's not clear at all what belongs where), you might need to remove the
else {} around that last return statement.
For fixing indentation (please do something like that before posting), you could use your editor's features or an online service like jsbeautifier.org
This message was deleted
no wiki entry for:
ceasars
This message was deleted
no wiki entry for:
ceasars cipher
help cipher
:point_right: algorithm caesars cipher [wiki]
:triangular_flag_on_post: Remember to use Read-Search-Ask if you get stuck. Try to pair program. :busts_in_silhouette: Write your own code. :memo:
:checkered_flag: Problem Explanation:
- You need to write a function, which will take string encoded with
Caesar cipher as a parameter and decode it.- The one used here is ROT13 where the value of the letter is
shifted by 13 places.
e.g. 'A' ↔ 'N', 'T' ↔ 'G'.- You have to shift it back 13 positions, such that 'N' ↔ 'A'.
:pencil: read more about algorithm caesars cipher on the FCC Wiki
//Setup
var contacts = [
{
"firstName": "Akira",
"lastName": "Laine",
"number": "0543236543",
"likes": ["Pizza", "Coding", "Brownie Points"]
},
{
"firstName": "Harry",
"lastName": "Potter",
"number": "0994372684",
"likes": ["Hogwarts", "Magic", "Hagrid"]
},
{
"firstName": "Sherlock",
"lastName": "Holmes",
"number": "0487345643",
"likes": ["Intriguing Cases", "Violin"]
},
{
"firstName": "Kristian",
"lastName": "Vos",
"number": "unknown",
"likes": ["Javascript", "Gaming", "Foxes"]
}
];
function lookUpProfile(firstName, prop){
// Only change code below this line
for (var i=0;i< contacts.length ; i++)
if(firstName===contacts[i][firstName]) {
if(prop===contacts[i][firstName].hasOwnProp(prop)) {return contacts[i][prop];}
else {return "No such property";} }
else {return "No such contact";}
// Only change code above this line
}
// Change these values to test your function
lookUpProfile("Akira", "likes");
You'll want to wrap your
for loop.
for (var i=0;i< contacts.length ; i++) {
if(firstName===contacts[i][firstName]) {
if(prop===contacts[i][firstName].hasOwnProp(prop)) {return contacts[i][prop];}
else {return "No such property";} }
else {return "No such contact";}
}
@ALMY91 :point_up: 15. April 2016 12:10
@Blauelf :package:
$.ajax({
url: 'http://api.forismatic.com/api/1.0/?method=getQuote&key=457653&format=json&lang=en',
success: function(data){
console.log("success ",data);
},
error: function(data){
console.log("error ",data);
},
type: 'GET'
});
this request providing proper response in postmaster but not in ajax call please guys help me
its shown error
url: 'http://api.forismatic.com/api/1.0/?method=getQuote&key=457653&format=json&lang=en',
success: function(data){
console.log("success ",data);
},
error: function(data){
console.log("error ",data);
},
type: 'GET'
});
this request providing proper response in postmaster but not in ajax call please guys help me
its shown error
@Blauelf hehe im doing it for the second time :smile:
$.ajax({
url: 'http://api.forismatic.com/api/1.0/?method=getQuote&key=457653&format=json&lang=en',
success: function(data){
console.log("success ",data);
},
error: function(data){
console.log("error ",data);
},
type: 'GET'
});its shown error
The error you're receiving is the cross-origin request being blocked?
This algorithm Caused me headache . Help me:
function truncateString(str, num) {
// Clear out that junk in your trunk
return str.slice(0, num);
}
truncateString("A-tisket a-tasket A green and yellow basket", 11);
You'll need javascript to treat the data being received as JSONP
@malangaveuday add the property 'dataType' with the value 'jsonp'.
seems like sleeping people here.
@Blauelf actually i didn really understood what you meant the last time tho
@InsaneSkull can u post a link to the challenge here
this is the code i have currently and i know the problem lies with me not having the quotations for the parameters but i dont really understand why. could u explain in layman terms?
```js
//Setup
var contacts = [
{
"firstName": "Akira",
"lastName": "Laine",
"number": "0543236543",
"likes": ["Pizza", "Coding", "Brownie Points"]
},
{
"firstName": "Harry",
"lastName": "Potter",
"number": "0994372684",
"likes": ["Hogwarts", "Magic", "Hagrid"]
},
{
"firstName": "Sherlock",
"lastName": "Holmes",
"number": "0487345643",
"likes": ["Intriguing Cases", "Violin"]
},
{
"firstName": "Kristian",
"lastName": "Vos",
"number": "unknown",
"likes": ["Javascript", "Gaming", "Foxes"]
}
];
function lookUpProfile(firstName, prop){
// Only change code below this line
for (var i=0;i< contacts.length ; i++) {
if(firstName===contacts[i][firstName]) {
if(prop===contacts[i][firstName].hasOwnProp(prop)) {return contacts[i][prop];}
else {return "No such property";} }
else {return "No such contact";}}