Get help on our basic JavaScript and Algorithms Challenges. If you are posting code that is large use Gist - https://gist.github.com/ paste the link here.
confirmed that this works:
but still would like to know how to regex parentheses!
inputTrimmed = inputLowercase.replace(/[^a-z0-9]/g,"");but still would like to know how to regex parentheses!
I had to use the octal codes - my final line looked like this:
thanks @kevinstonge :)
inputTrimmed = inputLowercase.replace(/\s|[,._-]|\050|\051/g,"");thanks @kevinstonge :)
sorry kevinstonge, you can't send brownie points to yourself! :sparkles: :sparkles:
@willcodes Sorry was offline
@sjames1958gm thank god, i've been so stumped lol. I had it at least changing the picture at one point when I called quotes[0].author
willcodes sends brownie points to @sjames1958gm :sparkles: :thumbsup: :sparkles:
:star2: 1923 | @sjames1958gm |http://www.freecodecamp.com/sjames1958gm
@kevinstonge Does
\( work for matching.
@sjames1958gm but i'm sure you know that wasn't the solution lol
@willcodes What do you have now
@Chrislearns Did you get help?
@sjames1958gm it honestly wasn't working for me, gave me a little yellow warning. :\ any idea what I might have done wrong?
@Chrislearns thats not inside a function right?
var random = quotes[Math.floor(Math.random() *quotes.length)];
function randomQuote() {
var random = quotes[Math.floor(Math.random() *quotes.length)];
$("#thisquote").text(random.quote);
$("#thisauthor").text("-" +random.author);
};
function changeBackground() {
var random = quotes[Math.floor(Math.random() *quotes.length)];
if ($(quotes[random].author) === "Kramer") {
$("body").css("background-image", "linear-gradient(to top, rgba(0,0,0,0.2), rgba(0,0,0,0.5)),url('file:C:/Users/user/Desktop/freecodecamp/random quote/images/kramer.jpg'");
}
else if (quotes[random].author === "George"){
$("body").css("background-image", "linear-gradient(to top, rgba(0,0,0,0.2), rgba(0,0,0,0.5)),url('file:C:/Users/user/Desktop/freecodecamp/random quote/images/george.jpg'");
}
else if (quotes[random]["author"] === "Elaine"){
$("body").css("background-image", "linear-gradient(to top, rgba(0,0,0,0.2), rgba(0,0,0,0.5)),url('file:C:/Users/user/Desktop/freecodecamp/random quote/images/elaine.jpg'");
}
else if (quotes[random]["author"] === "Jerry"){
$("body").css("background-image", "linear-gradient(to top, rgba(0,0,0,0.2), rgba(0,0,0,0.5)),url('file:C:/Users/user/Desktop/freecodecamp/random quote/images/jerry.jpg'");
}
else{
$("body").css("background-image", "linear-gradient(to top, rgba(0,0,0,0.2), rgba(0,0,0,0.5)),url('file:C:/Users/user/Desktop/freecodecamp/random quote/images/bg.jpg'");
}
};
/* function changeColor() {
var change = colors[Math.floor(Math.random() *colors.length)];
$('body').css("background", change);
$('#getQuote').css("background", change);
};*/
function removeHeader() {
$("#header").remove();
}
$('.btn').click(function() {
removeHeader();
randomQuote();
changeBackground();
});
});
@kevinstonge yellow warning in the FCC editor? Yeah not sure, maybe got confused matching parens?
ok, I went back and replaced my 050 and 051 with ( and ) and it worked. Weird. no clue what I did wrong.
lol
thanks @sjames1958gm
kevinstonge sends brownie points to @sjames1958gm :sparkles: :thumbsup: :sparkles:
:star2: 1924 | @sjames1958gm |http://www.freecodecamp.com/sjames1958gm
@willcodes If you calc random twice you will get different numbers
I figured it out
function rot13(str) { // LBH QVQ VG!
var string = str.split(" ");
var finished = "";
var map = Array.prototype.map;
var charCodeArray = map.call(str, function (x){
var y = x.charCodeAt(0);
if(y <= 77 && y >= 65){
y = y + 13;
}
else if(y >= 78 && y <= 91){
y = y - 13;}
return y ;
}); for(var i = 0; i<charCodeArray.length; i++){
finished += String.fromCharCode(charCodeArray[i]);
}
return finished;
}
@Chrislearns isnt that your problem its not inside a function so its not really being turne don ey?
@Chrislearns :+1:
@sjames1958gm let me remove the other 2 var randoms
@Chrislearns Here is how to get the post to show correctly :point_down:
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 thecode`.
See also: ☛ How to type Backticks | ☯ Compose Mode | ❄ Gitter Formatting Basics
@Chrislearns youg ot it working then?
@Chrislearns You could have done str.split("").map();
oh yea you can chain methods
@sjames1958gm
sweet
@sjames1958gm i just embeded it because as a global function it was stopping after one quote
@Chrislearns I see you had split(" ") which wouldn't split on characters is that why you didn't use string?
but it doesnt solve the problemo
@Chrislearns
for code posting - typing
you may also find the chat & compose buttons to the right of the chat text entry area useful. the backtick/s key is located to the left of the #1 (number one) key. :sparkles:
for code posting - typing
shift + enter provides additional line feeds (space for posting/pasting code).you may also find the chat & compose buttons to the right of the chat text entry area useful. the backtick/s key is located to the left of the #1 (number one) key. :sparkles:
```
function rot13(str) { // LBH QVQ VG!
var string = str.split(" ");
var finished = "";
var map = Array.prototype.map;
var charCodeArray = map.call(str, function (x){
var y = x.charCodeAt(0);
if(y <= 77 && y >= 65){
y = y + 13;
}
else if(y >= 78 && y <= 91){
y = y - 13;}
return y ;
}); for(var i = 0; i<charCodeArray.length; i++){
finished += String.fromCharCode(charCodeArray[i]);
}
return finished;
}
lol didn’t work
@Chrislearns Missed the ``` at the end. after shift-enter
Can you use .filter() on nested arrays?
@sjames1958gm
function rot13(str) { // LBH QVQ VG!
var string = str.split(" ");
var finished = "";
var map = Array.prototype.map;
var charCodeArray = map.call(str, function (x){
var y = x.charCodeAt(0);
if(y <= 77 && y >= 65){
y = y + 13;
}
else if(y >= 78 && y <= 91){
y = y - 13;}
return y ;
});
for(var i = 0; i<charCodeArray.length; i++){
finished += String.fromCharCode(charCodeArray[i]);
}
return finished;
}
nice
@Chrislearns :)
much easier
@DexPassenger yes.
@sjames1958gm Thank you.
dexpassenger sends brownie points to @sjames1958gm :sparkles: :thumbsup: :sparkles:
:star2: 1925 | @sjames1958gm |http://www.freecodecamp.com/sjames1958gm
@DexPassenger arr[i].filter() like that?
Yes exactly.
@willcodes put random = into your click handler and pass it to randomQuote and changeBackground if you make it global it may only be computing it once.
Title Case a Sentence - I feel like this is poorly written (but it works!) what could I do better here?
function titleCase(str) {
inputAsArray = str.split(" ");
outputString = "";
for (i=0;i<inputAsArray.length;i++) {
outputString += inputAsArray[i].charAt(0).toUpperCase() + inputAsArray[i].slice(1).toLowerCase() + ((i == inputAsArray.length - 1) ? "" : " ");
}
return outputString;
}
@kevinstonge if you build an array and use join you don't have to make that test as join doesn't put a " " at the end
Hi Guys I was doing following the instructions below .Here Is Instructions and code .On line 4 in instructions i could not get it . nextInLine([], 1) should return 1
nextInLine([2], 1) should return 2
nextInLine([5,6,7,8,9], 1) should return 5
After nextInLine(testArr, 10), testArr[4] should be 10
nextInLine([2], 1) should return 2
nextInLine([5,6,7,8,9], 1) should return 5
After nextInLine(testArr, 10), testArr[4] should be 10
so in my for loop I should push to an array and thena fter teh for loop I should join to a string?
@kevinstonge Yeah. Actually this is a good one for arraymap
function titleCase(str) {
return str.split(' ').map(function(val) {
return val.charAt(0).toUpperCase() + val.toLowerCase().slice(1);
}).join(' ');
}
@kevinstonge getting it right is 90% of the battle at this stage in the game ... even in pro development houses, you first get it right ... and you pick up how to do things better as you go along ... keep makin' progress, getting thru the challenges ... :)
bah, I thought of using map but couldnt' see how it would work!
function nextInLine(arr, item) {
// Your code here
var res = arr.push(1);
var res1 = arr.shift();
return res1;
}
nextInLine([5,6,7,8,9,10,1],1);
thanks again @sjames1958gm I'm going to try to use map without looking at your code :)
kevinstonge sends brownie points to @sjames1958gm :sparkles: :thumbsup: :sparkles:
:warning: kevinstonge already gave sjames1958gm points
thanks @bitgrower
kevinstonge sends brownie points to @bitgrower :sparkles: :thumbsup: :sparkles:
:star2: 1141 | @bitgrower |http://www.freecodecamp.com/bitgrower
@rahin1122 add item not 1
@kevinstonge It is good that you recognized that there might be a need for improvement. The code felt clunky and you felt it :)
@ndburrus Hey you are number one on points over the last 30 days - WTG.
@sjames1958gm thanks for noticing/commenting... now i need to refocus back to lessons & reading... :+1:
ndburrus sends brownie points to @sjames1958gm :sparkles: :thumbsup: :sparkles:
:star2: 1926 | @sjames1958gm |http://www.freecodecamp.com/sjames1958gm
I am completely lost on Record Collection, anyone have any advice on how to logically approach it? I'm stuck on the instructions and not knowing where to start.
And I've been staring at it for about a week.
@ndburrus Just starting on the React project for displaying this information
@sjames1958gm sounds interesting...
@AidenMead One of the campers has a nice description of it.
https://gist.github.com/revisualize/123deb77d85079f079020ac3cd6ea5ba
https://gist.github.com/revisualize/123deb77d85079f079020ac3cd6ea5ba
Wow, that almost makes it seem easy! Thank you @sjames1958gm
aidenmead sends brownie points to @sjames1958gm :sparkles: :thumbsup: :sparkles:
:star2: 1927 | @sjames1958gm |http://www.freecodecamp.com/sjames1958gm
@AidenMead @sjames1958gm That’s a good description. I was going to tell him to start with a simple if statement. That way he can get those synapses firing. Also go back over the previous challenges they have all the knowledge needed to get started. Learning how to connect the dots at that point is essential.
@sjames1958gm say, the link opens as an object...?
@sjames1958gm - my code for titleCase(str):
stringAsArray = str.split(" ");
fixedCaseArray = stringAsArray.map(function(val) { return val.charAt(0).toUpperCase() + val.slice(1).toLowerCase(); });
return fixedCaseArray.join(" ");I wonder if you'd mind commenting on how you know how much to stuff after the word 'return' because I see you put the whole damn function after the word return in your solution! Are there guidelines or rules for that?
@ndburrus Yeah that is the JSON input into the project -
Here is the sample project for the project
https://codepen.io/FreeCodeCamp/full/eZGMjp/
Here is the sample project for the project
https://codepen.io/FreeCodeCamp/full/eZGMjp/
I can see that I don't need to assign these things to variables if I'm not going to use the variables again ... I assume that's part of it
@Chrislearns I figured the key would lay in the previous lessons, but I keep writing out code that just accesses nested objects and then get stuck, haha.
@kevinstonge You kind of have to judge whether the beginning to end loses the meaning, if it does then you have to split it up.
There is a bit of a 'who can do it shortest' competition in this chat :)
There is a bit of a 'who can do it shortest' competition in this chat :)
@AidenMead lol
@Chrislearns @AidenMead there is a whole long discussion about the wording of that challenge.
FreeCodeCamp/FreeCodeCamp#9380
FreeCodeCamp/FreeCodeCamp#9380
Thanks
hi guys
@sjames1958gm lol I don’t blame them. When I first read it I winced myself.
it's definitely pretty rough
@sjames1958gm could you take a look at this and see why whenever i tweet out a quote.. there is a glitch and my main page goes to error
http://codepen.io/duel_drawer8/pen/WxdGzj
http://codepen.io/duel_drawer8/pen/WxdGzj
i ran into an issue with the word blank - cant understand what they wnat from me :))
@Dueldrawer8 The error I saw in your html is http:www.twitter.com/intent/tweet missing //
@sjames1958gm its there
window.open("http://www.twitter.com/intent/tweet?text=" + text + '-' + author);
})
window.open("http://www.twitter.com/intent/tweet?text=" + text + '-' + author);
})
@JohnMica have you read Mad Libs link yet?
@Dueldrawer8 html not js
yep
@sjames1958gm ah good point
@JohnMica review this challenge: https://www.freecodecamp.com/challenges/constructing-strings-with-variables
i assume is to build a quoting selfconstructing
thanks @Chrono79
johnmica sends brownie points to @chrono79 :sparkles: :thumbsup: :sparkles:
:star2: 1546 | @chrono79 |http://www.freecodecamp.com/chrono79
you have to build a string with the 4 parameters of you function and some more words @JohnMica
@sjames1958gm whenever i x out of the opened window the random quote page turns white?
@Dueldrawer8 Fixing that gives a different error I added target="_blank" to that a tag, and it looks like it breaks the contents of the tweet.
@Chrono79 I just started on the React project for displaying the highest ranking campers, you are number two on the recent list.
@sjames1958gm yeah it seems thats the solution.. thanks
dueldrawer8 sends brownie points to @sjames1958gm :sparkles: :thumbsup: :sparkles:
:star2: 1928 | @sjames1958gm |http://www.freecodecamp.com/sjames1958gm
@Dueldrawer8 Just remove the href from the a tag in the html and I think you are golden
@sjames1958gm :+1:
@sjames1958gm i think the json object isn't grabbing all the data. here is the data i'm seeing: https://fcctop100.herokuapp.com/
@ndburrus Hmm, interesting. That json is the link they provide in the project,
@sjames1958gm sweetness..tried to make it a little bit responsive as well..not much you can do with a box
How do you markdown again?
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 thecode`.
See also: ☛ How to type Backticks | ☯ Compose Mode | ❄ Gitter Formatting Basics
@JohnMica the exercise is asking for a sentence to be built using the 4 word types given. it may be easiest to begin by making a complete (spacing & punctuation) sentence, using the 4 words. to make sense, the complete sentence will require a few "filler" words. :sparkles:
@sjames1958gm Where do i add item 1 and how can i share the screenshot of codes.
@sjames1958gm one last thing, ive been trying to select the author in the blockquote and want to text-align : right.. which selector is it?
@rahin1122 item is the value passed in and posting code is right above :point_up:
function isLess(a, b) {
// Fix this code
if (a < b) {
return true;
} else {
return false;
}
}
// Change these values to test
isLess(10, 15);
@sjames1958gm what is the link? (if you have it handy...)
@Dueldrawer8 Not sure I get what you mean
Can anyone help me with this please? I'm trying to eliminate if else with an equality
@ndburrus which link?
@ndburrus I solved it - must be really late and cant make sense of it :))
this is the project https://www.freecodecamp.com/challenges/build-a-camper-leaderboard
thanks @ndburrus
johnmica sends brownie points to @ndburrus :sparkles: :thumbsup: :sparkles:
:cookie: 988 | @ndburrus |http://www.freecodecamp.com/ndburrus
@sjames1958gm in the random quote there is two text.. the actual quote and the author who says it. I want to shift the contents of the text of the author to the right
gitter could be too much improved :)
its like a modern IRC
@JohnMica you're welcome! excellent job :palm_tree:
just want to right align the authors name
@sjames1958gm Can you just write the full code for me .
@Dueldrawer8 If you use float:right it puts it way right
@rahin1122 Which challenge?
@sjames1958gm hm, alright thanks
dueldrawer8 sends brownie points to @sjames1958gm :sparkles: :thumbsup: :sparkles:
:warning: dueldrawer8 already gave sjames1958gm points
@rahin1122 Is it this challenge, the one about anti pattern?
if (condition) {
return true;
} else {
return false;
}can be replaced by
return condition@sjames1958gm Can you just have a look at my code and could you provide me a solution for this and I am just a new beginner in javascript ..function nextInLine(arr, item) {
// Your code here
var res = arr.push(1);
var res1 = arr.shift();
return res1;
}
nextInLine([5,6,7,8,9,10,1],1);
@sjames1958gm this is interesting. it appears that the links (listed in the exercise & that being used by the alternate source) are a little different. the alternate source link is: https://fcctop100.herokuapp.com for both local & session storage, while the exercise link offered adds (to the link mentioned) the following: /api/fccusers/top/recent (requirement #8) and /alltime (ending) (requirement #9). :sparkles:
@rahin1122 You should only use arr and item in your function - you are using arr, but you need to push item onto your array not 1
@ndburrus Interesting.
@ndburrus If you click on help score on that link you found it looks a lot more like the json.
@rahin1122 this may be helpful: :sparkles:
@ndburrus I think the project score (x50) is not in the json.
@sjames1958gm i think you're right - i'm not sure, but lesson (non x50) points may also not be included...
function largestOfFour(arr) {
var largestOfFourArray = [];
for (i=0;i<arr.length;i++) {
largestOfFourArray.push(arr[i].sort(function(a,b) { return b - a; })[0]);
}
return largestOfFourArray;
}
@cattman42 is it resolved?
also, there is a "markdown" button to the lower right of the chat text entry area that you may find useful. :)
also, there is a "markdown" button to the lower right of the chat text entry area that you may find useful. :)
and another one :)
function confirmEnding(str, target) {
return (str.substr(str.length-target.length) === target) ? true : false;
}
@rahin1122 is it resolved?
so I have a really general question about javascript objects and nesting and such, but I think if I can wrap my head around it, it may make more sense, and it revolves around the record collection challenge
@kevinstonge yes, in this line, just do this:
return str.substr(-target.length) === target; true or false is inferred
@Chrono79 - thanks! I didn't realize that would return true/false all by itself!
kevinstonge sends brownie points to @chrono79 :sparkles: :thumbsup: :sparkles:
:star2: 1547 | @chrono79 |http://www.freecodecamp.com/chrono79
hello can somebody help me with explaining the array method sort()?
I dont understand it and its very complicated to me
I passed the test but I want to know how
sort without any arguments will just sort from low to high or from a-z ... that's the easy part, I know...
the whole a, b
a -b, b - a, thing is very complicated lol
@jminchew97 it's a function that's used to compare two things
I dont understand it
alternatively you can include a compareFunction with a and b as arguments (a and be represent one item in the array and then the next item). whatever math you do with those items, if it returns a negative number, it will move a in front of b. it will loop through the array multiple times until it's all sorted
basically it applies that function to 2 items in the array
@jminchew97 don't know if it helps: http://www.w3schools.com/jsref/jsref_sort.asp
if the functionr returns a positive number
it'll swap them
swap?
otherwise, they'll remain in the same order relative to each other
move b in front of a
oh
let's say you have this simple, 2 item array
[2, 1]
and you sort it using the function
(a, b) => a - b
ohhhhhhhh
2 - 1 == 1, which is positive
so it swaps them
2 - 1 is negative
whereas if it was
[1, 2]
I gotcha
then it'd be
1 - 2 == -1
so it doesn't swap them
by the way I don't know why I said negative, lol.
So this applies no matter what?
:P I decided not to pay attention to it just to be polite
yes, this applies to all sort functions
no what what array?
here's another example:
let foo = ["bazinga", "bingo", "baz", "quux"];
foo.sort((a, b) => a.length - b.length)
^ that will sort the strings in ascending order based on their length
doesn't matter what the array is, what it contains, it just follows those simple rules.
I think I've gotten the hang of it.
At least better than I did before.
This message was deleted
Anyone have insight into the resolving the card counting problem. Just a direction is needed
Hey Jason I can try to help you out
evaluate card value and modify count value in one block, evaluate count value and return in another block @JasonSooter
Sounds good @jminchew97
@JasonSooter actually I think @Chrono79 is more experienced than me! So I'll let him help you.
@Chrono79 I've got the first part. Is a switch the best method?
Hello all! Can anyone explain why parseInt is used in the answer for the 'Where do I belong challenge?
function getIndexToIns(arr, num) {
// Find my place in this sorted array
arr.sort(function(a, b){
return a - b;
});
for(var i = 0; i<arr.length; i++){
if(arr[i] >= num){
return parseInt(i);
}
}
return arr.length;
}
getIndexToIns([1, 2, 3], 15);
@JasonSooter switch or if/else, your choice
Ok. Got that part. Wondering about the sequencing part though. Am checking them as an array?
@labanch dunno, I think it works without it too
@JasonSooter you evaluate just 1 card at a time in your function, in the tests, it's called several times
@Chrono79 yeah it does. I thought parseInt only accepted strings so I was a bit confused on why it would pass with that
Ok. got it. I was thinking about the objectives wrong. Thanks for your help.
function truncateString(str, num) {
return ((str.length <= 3) ? str.slice(0,num) + "..." : (num <=3) ? str.slice(0,num) + "..." : (num >= str.length) ? str : str.slice(0,num-3) + "...");
}
please I need some help, this method doed nto print myFather.name:
that works, but could anyone show me their truncate a string code??
@kevinstonge
function truncateString(str, num) {
return num<str.length ? str.slice(0, num<=3 ? num : num -3)+"..." : str;
}
oh I knew mine was shit :) thanks @Chrono79 I'm going to study that
kevinstonge sends brownie points to @chrono79 :sparkles: :thumbsup: :sparkles:
:warning: kevinstonge already gave chrono79 points
this is blowing my mind ... how do you learn to code like that?
i am stuck on the challenge 'Record collection' for JSON objects
can anyone help me?
refactoring @kevinstonge and trying to keep it dry
I'm stuck on the same @clydebaron2000
dry?
dry: don't repeat yourself, if you look at your code you'll see the same repeated
str.slice(0,num) + "..."
yeah, that's what makes it ugly .. I just can't muster the brain power to merge all of that into one tiny line like you did.
one thing I can apply from your code is putting the conditional statement as an argument. I've never done that. I can use that in the future pretty easily. :octopus:
:+1:
@Chrono79 do you generally write your code out in longer form and then go back and refactor?
sometimes, yes, it's better to do it longer first and then trying to shrink it
You should make a youtube series on JS :smile: @Chrono79
hey guys do u like this effect? http://codepen.io/dagman/full/qNpJgN/
So I'm stuck on adding an array to an object, I can't figure out the correct syntax to do so.
@AidenMead adding how?
you really have to be specific, because in javascript, stuff like this is not an error:
[1, 2, 3, 4, 5] + {a: 1, b: 2}
// -> '1,2,3,4,5[object Object]'
is there a way to push things to the output/codeMirror for testing? For example: can I do a console.log and check a variable's value?
In record collection, the instructions read " If prop is "tracks" but the album doesn't have a "tracks" property, create an empty array before adding the new value to the album's corresponding property."
just assign to its
tracks property
let object = {a: 1, b: 2, c: 3};
if (!object.hasOwnProperty("tracks")) {
object.tracks = [];
}
object.tracks.push(5);
// -> {a: 1, b: 2, c: 3, tracks: [5]}
the important line there is
object.tracks = []
I feel your pain @AidenMead - this one is hurting my brain too
if (prop === "tracks" && value === "") {
collection[id].tracks = [];
does that look right?
This isn't showing anything in the code window.
var testProp = collection.hasOwnProperty(prop);
console.log ("testProp = " + testProp);Why is that?
well syntactically it looks fine, but
if
value is empty, you're supposed to delete the property
@jfx1026 that little window isn't console output
it's what your function returns
right, which I don't particularly understand, these instructions are rough, haha.
ok, so - how do I test a variable to see if it's actually doing what I think it should be?
ohhh, do I need to nest if/else statements to get it to effectively do both or none?
is that what I've been missing? hmmm
Nope, that's not working
It's just that one that I can't get at all
@AidenMead - this is my mess, maybe we can help each other
function updateRecords(id, prop, value) {
var testProp = collection.hasOwnProperty(prop);
//console.log ("testProp = " + testProp);
if (testProp===false) {
collection[id][prop] = value;
if (prop === "tracks" && value === "") {
//collection[id].tracks = [];
var object = {a: 1, b: 2, c: 3};
//set tracks
if (!object.hasOwnProperty("tracks")) {
object.tracks = [];
}
object.tracks.push(5);
}
} else {
return "WTF!";
}
return collection;
}
It's not working, so I don't know
haha, I like your second to last return
this nested If is not doing anything for me
I have a question about the increment lesson on Javascript. I'm using the ++ and it just doesn't want to take it
I used stuff like :
if (value !== "" && prop !== "tracks") {
collection[id][prop] = value;
And it seems to be working well so far, I have all but one of the test inputs testing out correctly, it's just the one "After updateRecords(5439, "tracks", "Take a Chance on Me"), tracks should have "Take a Chance on Me" as the last element." that's still returning negative.
I like the use of the && here, super logical - I just can't seem to make the mental leap to do something with the code after that
that one is failing for me also
So I was in the chat earlier and a couple of people led me to a link where there was a discussion about the instructions and how the old wording worked better, so I approached it with that.
Nevermind - though the lesson example is a little misleading
// Write a function which takes:
// an id, a property (prop), and a value.
function updateRecords(id, prop, value) {
// If value is non-blank (value !== "")
// and prop is not "tracks"
// then update or set the value for the prop.
// Your code here
// If the prop is "tracks" and value is non-blank,
// push the value onto the end of the tracks array.
// Your code here
// If value is blank,
// delete that prop.
// Your code here
// Always return the entire collection object.
return collection;
}
@AidenMead I know that you can't push with a JSON object, you have to use dot/bracket notation only
thanks for the look on that
Ohhh, hmmmm, maybe that's the issue I'm running into
I did use push
you can only push an Array - a coder friend tells me that JS doesn't use true Arrays, but you can create them.
So I tested that, took out my .push() line, and set it equal to the new value, and it actually caused a couple of the tests to come back negative.
SORRY! Undo, quick.
haha, no worries
I've been messing with it so much that I took my original solution (that gave me the most positives) and posted it in notes for safe keeping so I can play around.
Here's what I've got:
function updateRecords(id, prop, value) {
if (value !== "" && prop !== "tracks") {
collection[id][prop] = value;
} else if (prop === "tracks" && value !== "") {
collection[id].tracks.push(value);
} else if (value === "") {
delete collection[id][prop];
}
return collection;
}
thanks, still plugging away
however, when I run a test involving the .push() condition, i am actually getting an error
is it bad that it took me a half hour to figure this out?
function chunkArrayInGroups(arr, size) {
var j = Math.ceil(arr.length/size - 1);
for(i=0;i<=j;i++) {
arr.splice(i,size,arr.slice(i,i+size));
}
return arr;
}is there an easier way that I overlooked?
hi guys
am working on local weather app presently, I got my coordinates using geolcation object on JSFiddle but when I did same thing on codepen it didn't work, what might be the problem?
am working on local weather app presently, I got my coordinates using geolcation object on JSFiddle but when I did same thing on codepen it didn't work, what might be the problem?
@Lumexralph using chrome?
@Lumexralph and do you have a link? It could be a bunch of things but its probably related to https vs http
yes, am using chrome but working on both JSFiddle and Codepen, should there be any issue?@Benalron
If you are using Chrome then it probably has to do with HTTPS. Here is a link to the doc that explains why it will not work. https://developers.google.com/web/fundamentals/native-hardware/user-location/obtain-location?hl=en
@Lumexralph
Sorry. That was intended for
@jfx1026 i found another way to get to the same spot that I'm in, with the same test input coming back negative. You having any luck?
function testLogicalAnd(val) {
// Only change code below this line
if (val <= 50) {
if (val >= 25 ) {
return "Yes";
}
}
// Only change code above this line
return "No";
}
// Change this value to test
testLogicalAnd(24);
if (val <= 50 && val >=25) { ...
you are combining both if statements into one
@AidenMead - rebuilt everything again and I'm in the same place - I think I'm getting closer though
I'm getting this error though now : collection[id][prop] = value;
@kevinstonge Thanks I did that but was missing the second Val. Thanks for the help
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TypeError: collection[id][prop] is undefined
@jfx1026 can you post your code?
can anyone tell me why this code doesn't work? Trying to solve seek and destroy
I finally got it, had to re-write a line of code and post in in twice to work with my if/else statements without one contradicting the other, it seems
the error was caused my throwing in the failing test request - when I use any other the code works (without passing the one test)
That same thing was happening to me, I was stuck with the silly track "Take a Chance On Me" not returning positive.
But I would only get an error when I actually put in those test variables, otherwise it came back fine.
I've got the reverse - the one with "Free" is failing on me now
the 5th test
in "Escape Sequences in Strings" Assignment I am codding this but it is giving error
var myStr = "FirstLine \n \ SecondLine \ \r ThirdLine"; // Change this line
code here
function updateRecords(id, prop, value) {
if (value !== "" && prop !== "tracks") {
collection[id][prop] = value;
} else if (prop === "tracks" && value !== "") {
collection[id].tracks = [];
collection[id][prop].push(value);
} else if (value === "") {
delete collection[id][prop];
}
return collection;
}
// Alter values below to test your code
updateRecords(2468, "tracks", "Free");
hi guys! I'm stuck at the mad libs problem... I have absolutely no diea what to do or even where to start
can any body help
I realized that we were both pursuing the right track, but seperately, so .hasOwnProperty is a factor
@AidenMead if I comment out 'collection[id].tracks = []; - the failed test switches from 5 to 2
what is wrong in this codding
Hey, I'm doing the Global vs. Local scope functions. I'm not sure why my code isn't working:
// Setup
var outerWear = "T-Shirt";
function myOutfit() {
// Only change code below this line
var myOutfit = "sweater";
// Only change code above this line
return outerWear;
}
myOutfit();
Yeah, that's where i realized the nested if/else statements came in, but also the .hasOwnProperty
Challenge is
Do not change the value of the global outerWear
myOutfit should return "sweater"
Do not change the return statement
if (value !== "") {
if (prop !== "tracks") {
collection[id][prop] = value;
} else if(!collection[id].hasOwnProperty("tracks")) {
collection[id].tracks = [];
collection[id][prop].push(value);
@MalickArsalan - check the markdown help for posting your code
In 'Seek and Destroy' the first step is to store the arguments in an array? Am I right?
@jfx1026 i dont get it
@TheJamieCrawford it appears that you are trying to change the function name.. "myOutfit" is the function, whereas the variable "outerWear" is the variable that "myOutfit" it looking to change
@AidenMead I don't understand >.<
if you type three of these
, then paste your code and three more, then your code will show up in black, like everyone else here - no screen shot needed
ok
the key is the same as the ~, without shift
```
// Setup
var myObj = {
gift: "pony",
pet: "kitten",
bed: "sleigh"
};
function checkObj(checkProp) {
// Your Code Here
myObj.hasOwnProperty("gift");
return "pony";
}
// Test your code by modifying these values
checkObj("gift");
var myStr = "FirstLine\n\\SecondLine\\\ThirdLine"; // Change this line
@AidenMead I figured it out :dancer:
Testing Objects for Properties
thanks @AidenMead
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Thanks :) @jfx1026
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what is wrong in this code
var myStr = "FirstLine\n\\SecondLine\\\ThirdLine"; // Change this line
@TheJamieCrawford So look at each name, they are separate variables. So on the outside, you wear a t-shirt. The t-shirt is part of the outfit. One a very simple level, we need to do something to change the t-shirt, or "outerWear" because it's too cold. So we do something (a function labelled the general term"myOutfit") to change the outerWear. The way you have it set up, you're taking the function "myOutfit" and trying to change it, where you should be trying to change "outerWear".
in Escape Sequences in Strings task
Sorry if that makes it more confusing, haha. Trying to explain without re-writing the code ;)
@TheJamieCrawford Just saw you figured it out up a bit :+1:
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hi guyz
my weather app so far
can someone tell me why it doesnt return the weather ?
@MalickArsalan - I'm looking back at mine, one sec
Sure @jfx1026
@MalickArsalan - mine is failing the same first test as yours
var myStr = "FirstLine\n \\\SecondLine\\\ \rThirdLine";
I must have completed this one on my machine at work and it's not saved here
ok Thanks for your Effort :)
:)
@jfx1026 - Thansk Alot
can anyone else help out on this one - https://www.freecodecamp.com/challenges/escape-sequences-in-strings
@AidenMead - I finally got it, it's not pretty though
thanks @AidenMead for your tips
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Need help with falsy bouncer. here's my code. i only get 1/4 of the tests.
function falsy(value) {
if (value === false || value === null || value === 0 || value === undefined || value === "" || value === isNaN) {
return value;
}
}
function bouncer(arr) {
// Don't show a false ID to this bouncer.
return arr.filter(falsy);
}
bouncer([7, "ate", "", false, 9]);
@jod29 I'm stuck on the same one. One thing I'm finding is that isNaN literally means "is not a number" so it will filter things like "ate" because "ate" is not a number.
function testLogicalOr(val) {
// Only change code below this line
if (val > 10 || val < 20) {
return "Outside";
}
{
return "Inside";
}
// Only change code above this line
return "Inside";
}
// Change this value to test
testLogicalOr(10);
@kevinstonge been stuck for 3 days now :)
my code only gets the first two:
function bouncer(arr) {
return arr.filter(function(val){return (val===false||val===""||val===null||val===0||val===undefined) ? false : true; });
}
i only get the third one
@jfx1026 - I have done but not sure what was my mistake in previous which was
var myStr = "FirstLine\n\\SecondLine\\\ThirdLine"; // Change this line and var myStr="FirstLine\n\\SecondLine\\\rThirdLine";
and now*
@jod29 rather than specifying every kind of falsy value to filter out, try only returning truthy values. check it: https://repl.it/Ccmi
@qualitymanifest thank you!!!
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tnx @qualitymanifest
np
here's my code for that one now!
function bouncer(arr) {
return arr.filter(function(val){return (val); });
}
I hate how simple it was :)
@TommyIzen
can anyone tell me why this code doesn't work? Trying to solve seek and destroy
https://repl.it/CcmR
can anyone tell me why this code doesn't work? Trying to solve seek and destroy
https://repl.it/CcmR
@kevinstonge you could also return !!!!!!!!!!!!!!!!!!!!val, so long as it was an even amount of exclamation points, haha.
@qualitymanifest I'm really surprised that works for the number 0.
I think that's what stopped me from even trying it that way
@kevinstonge @qualitymanifest (head spinning) haha! that was clever!
@TommyIzen you're going to need to use the
arguments object again on this one, and you don't want to convert it to a string
function testLogicalOr(val) {
// Only change code below this line
if (val > 10 || val < 20) {
return "Outside";
}
// Only change code above this line
return "Inside";
}
// Change this value to test
testLogicalOr(25);```
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@Mrblue27 My bad, are you writing a function that checks if
val is > 10 AND <20?
@Mrblue27 greater than/less than's are reversed
@Mrblue27 If so, you need to change
|| (OR operator) into && (AND operator)
@alchermd that's not the case, the name of the function is testLogicalOr
@qualitymanifest Whoops. Have you solved it yet? What was the expected result for
testLogicalOr(25) ?
@alchermd No worries, totally understandable why you would want to check. Anyway, that should return Outside. this is the challenge https://www.freecodecamp.com/challenges/comparisons-with-the-logical-or-operator
@qualitymanifest Gotcha. It's quite confusing for me without understanding the context of the problem haha
yeah for sure. i generally just ask people to link to the challenge so i can see what's expected
@qualitymanifest In any case, I'm looking for some help too! Are you by any chance knowledgeable in RegExp?
@alchermd somewhat. what's up?
hi guys, can anybody point out why I am not able to get weather info after I select city from the list box. here is my codepen : http://codepen.io/pragyesh31/full/PzERaV/
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@qualitymanifest Here's what's up:
I'm currently on the Validate Us Numbers challenge
https://www.freecodecamp.com/challenges/validate-us-telephone-numbers
I'm aware that there's a bunch of RegExp challenges that I already passed, though I used some obscure long If-Else chains that checks for each value of the string. I guess this is the perfect challenge for me to really learn RegExp.
Would you mind guiding me step by step on what should I do in this challenge?
@alchermd so my solution to this ended up being a one-liner, and i wrote some pseudocode to help explain what's going on. i'll give you that pseudocode... one sec
here:
Allow a 1 and a space, then area code with BOTH parens or NO parens, then allow a space/dash, three more numbers, allow another space/dash, then the last four numbers. Nothing before or after
(parens === parenthesis)
ty @qualitymanifest
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i agree, this is a very good challenge to learn regex, and is worth taking the time to really figure out. if you're not familiar with using regex101.com for testing, check that out. if you haven't been through regexone.com 's tutorial, check that out. even after that tutorial you will probably still need to refer to MDN docs on regex quite a bit, to solve that one efficiently @alchermd
@kirbyedy did i do something for you or are you just passing out brownies to be nice?? also, dang that's quite a streak you've got!
Would anyone care to spare a moment to help me understand APIs? I literally can't even.
@qualitymanifest Thank you for the help mate! Just another one: let's say I successfully built my RegExp, what JS function do I pass it on to check if it matches
string ?
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@alchermd np.
regex goes here.test(str)
@qualitymanifest Gotcha. I'll get back to you if I have further questions! :D
I'd like some tips on "Seek and Destroy" - the following code works, but it can't possibly be the best way to do this:
var globalArguments = [];
function destroyer(arr) {
globalArguments[0] = arguments[1];
globalArguments[1] = arguments[2];
globalArguments[2] = arguments[3];
return arr.filter(function destroyFilter(val){return (val===globalArguments[0]||val===globalArguments[1]||(globalArguments[2]&&val===globalArguments[2])) ? false : true;});
}
I know a for loops seems to make sense, but it got mad at me for defining a function inside the for loop :\ ... the filter function.
@kevinstonge I guess you can use
in method of Array to check if val is in globalArguments to shorten your code.
@kevinstonge the compiler complains about making a function inside of a loop, but it will still work. Its how I did it. I'd show you my code for comparison, but it seems to be missing
Hey! I have coded this solution for 'Seek and Destroy'. What do you think? Is it a good approach or not? Please tell.
function getIndexToIns(arr, num) {
// Find my place in this sorted array.
var array = [];
array = arguments[0];
array.push(num);
array.sort(function sortArr(a, b)
{
return a - b;
});
return array.indexOf(num);
}
getIndexToIns([40, 60], 50);
@kevinstonge And there's no need in naming the callback function. You're not going to use it in your code anywhere except that
filter function, right?
@kevinstonge are you familiar with indexOf?
@qualitymanifest its for the hint about that telephone number challenge
@faisal1337 it's fine but it's not good practice to name a variable "array". also you don't even need to make that variable... just use
arr which is passed into the function
Thanks. Lemme change it.
:thumbsup:
@qualitymanifest Is it a good practice when you change a function arguments inside that function?
And the solution was for 'Where do I belong'. Mistake :D
@faisal1337 Interesting idea of finding a place for a num.
Ahan.
@lx-t in this case, i don't see why not. you're changing it for one specific purpose, and you don't need it after that. and i was only recommending against calling a variable "array" because its a reserved word.
function destroyer(arr) {
globalArguments = arguments;
return arr.filter(function(val){return (val===globalArguments[1]||val===globalArguments[2]||val===globalArguments[3]) ? false : true;});
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correction, not a reserved word, but close enough.
Can someone help me on the golf app waypoint
@kevinstonge are you familiar with indexOf?
@qualitymanifest yes but I'm not sure how to use it in this situation
str.indexOf(searchValue[, fromIndex])
@qualitymanifest I didn't know that JS can change arguments and it costed me some time to debug my script. Now, I'm avoiding changing arguments inside a function. :)
@kevinstonge make a real array of the additional arguments (the ones that come after
arr). then run a filter on arr, removing the pieces of arr that are present (indexOf !== -1) in your newly made arguments array
function getIndexToIns(arr, num) {
// Find my place in this sorted array.
arr.push(num);
arr.sort(function sortArr(a, b)
{
return a - b;
});
return arrindexOf(num);
}
Changed it.
function getIndexToIns(arr, num) {
// Find my place in this sorted array.
arr.push(num);
arr.sort(function sortArr(a, b)
{
return a - b;
});
return arr.indexOf(num);
}
@qualitymanifest I mean, I was surprised that a function's arguments do not belong to local namespace of a function like in some other languages.
thanks @faisal1337
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@lx-t hm, i see what you're saying, i haven't had problems with that yet... let me test that out real quick
Hey guys! How do i run two separate loops at the same time?
function golfScore(par, strokes) {
// Only change code below this line
if (strokes == 1) {
return "Hole-In-One!";
} else if (strokes <= par - 2) {
return "Eagle";
} else if (strokes == par - 1) {
return "Birdie";
} else if (strokes == par ) {
return "Par";
} else if (strokes == par + 1) {
return "Bogey";
} else if (strokes == par + 2) {
return "Double Bogey";
} else if (strokes >= par + 3) {
return "Go Home!";
}
// Only change code above this line
}
// Change these values to test
golfScore(4, 1);
how is this wrong?
@qualitymanifest isn't that basically what my code does? I just use an equality to check each argument instead of checking if the index is not -1.
@NeliusKnight try checking the return spellings. FCC wants it to be exact
if its still wrong, let me know
Ive been on this waypoint for 3 days
and THAT was the problem?!
@kevinstonge yes, but using an array of the other args and indexOf is less verbose, and, much more importantly, keeps you from having to hardcode in the number of extra arguments to filter
@NeliusKnight did it work?
it sure did @Cal-culator thank you
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:warning: could not find receiver for cal-culator
@qualitymanifest I'm not understanding - can you show me your code for that challenge?
geez...
3 days just to find out it was because of capitalization
@NeliusKnight No worries. I always check the spelling from then on after that.
@lx-t alright, you have a good point, thanks
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After I finish the Front End Section of FCC. What will be my level in JS. Beginner or Intermediate?
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yeah, I don't understand the e1 => part
why did you delete it? :)
hey all
i don't like to leave solutions up... someone else might come by who is working on that and see the spoiler. anyway => is basically shorthand for function() {}
need some help with the roman numeral converter
@kevinstonge so, make an array of the additional arguments. filter arr to remove pieces that are present in the additional elements
(piece of arr.indexOf(additional element array) === -1
err !== -1
Any suggestion on how to start? I'm thinking of a named array, with the character codes for each roman numeral from 1 - 9, 10, 50, 100, 500, and 1000
@Torgian basically yeah. make two arrays containing equivalent numbers and roman numerals at the same index. or one two-dimensional array. don't forget about 4, 9, 40, 90, etc, as those ones go by a slightly different pattern than the rest
TypeError: str.split("").toLowerCase is not a function. (In 'str.split("").toLowerCase()', 'str.split("").toLowerCase' is undefined) How do i fix this?
Well, this is what i have, using char codes for the available roman numbers (HTML char codes)
@Torgian oh, no. no need for HTML char codes
might have to change that to just regular letters
ah ok
Was thinking of using the numbers as "keys" so to speak
@Cal-culator lowercase before splitting
@Cal-culator can't lowercase an array
or ids
@qualitymanifest that => is somehow allowing you to access arguments from destroyer inside of your filter function ... but I think I understand how it works outside of that => thing! Thank you!
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Here is how I had to modify it to make it work:
function destroyer(arr) {
globalArguments = arguments;
return arr.filter(function(val){return Array.from(globalArguments).indexOf(val) === -1;});
}
@qualitymanifest ah ok. thanks
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@kevinstonge :+1: that is pretty much how i would do it in es5. only nitpicky things: it would be good to assign globalArguments with
var in front of it, and if you made it an Array at the same time as you assigned it, it wouldn't have to make a new Array on each iteration of the filter, so would be a little more efficient
var globalArguments = arguments;
doesn't that already make it an array since arguments is an array?
@Torgian i guess you could use the numbers as keys for the actual roman values
1: "I", 4: "IV" etc. but you're trying to make an object by wrapping it in [] when you should be wrapping it in {}. also, i think this one is just easier with arrays rather than objects
I want to replace all special characters with " ". Do I have to type all special characters manually or is there a term?
@kevinstonge
var globalArguments = Array.from(arguments)
oh I see
@kevinstonge
arguments is an array-like object (has numeric properties and .length property), but no array methods.
@kevinstonge then change it slightly inside the filter. it's a little more efficient, but nitpicky, you got the gist of it well
got it, thanks again :)
thanks @Blauelf
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@faisal1337 All functions have .call(), .bind(), and .apply() methods that change how a function is called. The .call() method can determine the calling object (thisArg, the value of this inside the method) and also arguments passed into the method. If call() is used on an array method, the thisArg can be an array like object (needs to have numeric properties
"0", "1" etc and .length property). So .call() allows calling array methods on array-like objects like strings (string wrappers are array-like), arguments objects, nodelists, etc. Also on your own array-like objects.
@Masd925
var x =new Boolean("null"); //I understand
if (x) console.log(1);
var y =new Boolean(null); //should'nt execute
if (y)console.log(2); //but does.why ??how do I know when I can chain methods and when I can't?
For example this works:
arr.sort().indexOf(n);
but this doesn't work:
arr.push(i).indexOf(n);
@kevinstonge because arr.sort returns an array on which indexOf works
@qualitymanifest Hey mate, so something like this you think? For the array?
@chaitanyaashtekar
if coerces values to Boolean type, so all objects coerce to true.
@kevinstonge but
arr.push(i) doesnt return an array
thank you @chaitanyaashtekar that makes sense
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@chaitanyaashtekar @Masd925 is right. use
Boolean rather than new Boolean
~
@chaitanyaashtekar If you need to coerce a value to Boolean type, you should use the Boolean function
Boolean(val).
do you know of a shorthand way to stuff push and indexof into the same line? like that? :)
well you could use
.concat but that won't modify the array in place like .push does
@Masd925 okay. but from the mdn website----
Any object whose value is not undefined or null, including a Boolean object whose value is false, evaluates to true when passed to a conditional statement
`[1, 2, 3, 4].concat(5)
damnit
@llamatarianism i know but im asking it to clear my concept
[1, 2, 3, 4].concat(5).indexOf(5); @kevinstonge
@chaitanyaashtekar Read it again. It is the same that I said.
function palindrome(str) {
// Good luck!
var a=str.toLowerCase().replace(/[^A-Z0-9]+/ig, "").split("");
var b=str.toLowerCase().replace(/[^A-Z0-9]+/ig, "").split("").reverse("");
for (var i=0; i<a.length;i++){
if (a[i]===b[i]){
return true;
}
else if (a[i]!==b[i]){
return false;
}
}
}
palindrome("almostomla");
@Masd925 yes.okay. thank you !
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@chaitanyaashtekar in your example
y isn't false
it's an object that has a value of false
@llamatarianism ahhh.thanks man !
@llamatarianism thanks !
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@Cal-culator your function only checks the first 2 letters
Thank you @llamatarianism got my one line function with that concat tip :)
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return == break
@llamatarianism what do you mean?
can you elaborate
your loop always returns on the first iteration
and returning ends the loop
oh... i see
so you only check the first letters
@llamatarianism how do i fix it? Do i make another loop at the bottom to check?
@Cal-culator dont return
true when char are equal.let the loop continue.return false only when you find them not equal
here's what you do:
@Cal-culator ```
for (var i=0; i<a.length;i++){
if (a[i]!==b[i]){
return false;
}```
damm
use
.join to make a and b into strings
@Cal-culator ```
for (var i=0; i<a.length;i++){
if (a[i]!==b[i]){
return false;
}```
then compare those strings
this challenge does not need a for loop
@chaitanyaashtekar thanks
@llamatarianism thanks
```
function palindrome(str) {
// Good luck!
var a=str.toLowerCase().replace(/[^A-Z0-9]+/ig, "").split("");
var b=str.toLowerCase().replace(/[^A-Z0-9]+/ig, "").split("").reverse("");
for (var i=0; i<a.length;i++){
if (a[i]===b[i]){
}
else if (a[i]!==b[i]){
return false; break;
}
}
return true;
}
palindrome("almostomla");
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yes you could just use
====
function palindrome(str) {
// Good luck!
var a=str.toLowerCase().replace(/[^A-Z0-9]+/ig, "").split("");
var b=str.toLowerCase().replace(/[^A-Z0-9]+/ig, "").split("").reverse("");
for (var i=0; i<a.length;i++){
if (a[i]===b[i]){
}
else if (a[i]!==b[i]){
return false; break;
}
}
return true;
}
palindrome("almostomla");
It worked
@llamatarianism try
return a===b no need of for loop
actually comparison doesn't work that way for arrays
[1, 2, 3] !== [1, 2, 3] because they're different objects
the solution is, like I said, to make them into strings
then compare them
yes.but they are strings.so it will work
no they're not
ahh.you are right .he didnt
.join them later.i didnt read correctly
thanks @llamatarianism
:warning: chaitanyaashtekar already gave llamatarianism points
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Hello folks.
I'm trying to understand, 'Nesting for loops'. I got a working solution, but I don't understand what 'j' is doing.
function multiplyAll(arr) {
var product = 1;
// Only change code below this line
var array = [arr];
for (var i=0; i < arr.length; i++){
for (var j=0; j < arr[i].length; j++){
product = 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]]);It looks like 'j' is checking the length of the container array and then moving to the next item. However, how is it moving in and out of each of the nested arrays [0], [1] and [2]?
I think j is looping through each element of the specified array
because you have array of arrays
@leebut
arr[i] is one subarray and j loop loops through its indices.
TypeError: str.toUpperCase.split is not a function. (In 'str.toUpperCase.split(" ")', 'str.toUpperCase.split' is undefined)
@Cal-culator
.toUpperCase().split()
@Masd925 ah ok thanks
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Hey guys, in 'Wherefore art thou' intermediate algorithm scripting I'm getting
ReferenceError: keys is not defined while using sourceKeys = Object.keys(source);. Can anyone tell me why?
@KamilMalek Code seems right. Where are you testing it?
Right in the fCC code editor
Try refreshing the page.
All right
inside the function right?
Yes
Refreshing didn't help
@Masd925 does that mean the line italics product = product arr[i][j]; * is using [i] to count the index of the container array and [j] is counting the indices of the nested array?
Here's the whole snippet:
function whatIsInAName(collection, source) {
// What's in a name?
var arr = [];
// Only change code below this line
// There was a for loop involved. The first part involved getting the keys from the source
sourceKeys = Object.keys(source);
return collection.filter(function (obj){
for(var i = 0; i < keys.length;i++){
if(!obj.hasOwnProperty(sourceKeys[i]) || obj[sourceKeys[i]] !== source[sourceKeys[i]]) {
return false;
}
}
return true;
});
}
// Only change code above this line
@leebut Yes, i means the arr element index (elements of arr are arrays).
@KamilMalek put var before sourceKeys
@Athaman Still nothing
And I tested in on a different machine just to make sure
oh wait, it's the keys.length in your for loop
@Athaman Oh my god, thanks
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Such a stupdi one
Thank you :)
hah, it happens :D
@Masd925 Thank you. I partially understand it. I'm thinking that var product should be defined globally to make it accessible to console.log() or document.GetElementById("id").innerHTML = ;
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Why does this happen?
TypeError: a[i].join is not a function. (In 'a[i].join("")', 'a[i].join' is undefined)
TypeError: a[i].join is not a function. (In 'a[i].join("")', 'a[i].join' is undefined)
function titleCase(str) {
var a= str.split(" ");
var b=[];
var c=[];
var d=[];
for (var i=0;i<a.length;i++){
b=a[i].split("");
b[0].toUpperCase();
c.push(b[0]);
d= c.join("").toUpperCase().split("");
b[0].replace(d[i]);
a[0].replace(d[i]);
a[i].join("");
}
a.join(" ")
console.log(a);
}
titleCase("I'm a little tea pot");
@Cal-culator don't put the brackets...it shud only be a.join("");
Which join? the one inside the loop?
@ekleung123
wait...did u mean a[i].push?
by doing a[i].join, you're saying only to join one element in the array, which wouldn't make sense
@ekleung123 If i write a.join(""), wouldn't it mean join all of the words together?
I just want it to join words together
doing a.join("") would convert the array into a string
@ekleung123 let me try that
["apple","boy","cat"] becomes "apple, boy, cat"
With just .join(""), it becomes
'appleboycat', but you can define the delimiter as you like.
can you help me ?
Hello. My name is Chris. I'm having a big issue with my hangman game that I feel like should have been simple. Can anyone help? I am trying to append the user's input(a single letter) to one of the underscores(which represents a missing letter). https://jsfiddle.net/jtpsj5eu/16/
my code run out is good ! but it con't ?why ?
function repeat(str, num) {
// repeat after me
if(num<0){
return "";
}
else {
var strs = "";
for(var i=0;i<num;i++){
strs +=str;
}
return '"'+strs+'"';
}
}
repeat("abc", 1);
@Cal-culator You're also not using the replace method propertly. In the replace method, you have to tell what you want to replace and what you want to replace it with. Example: string.replace("this","that");
@ekleung123 Ah ok
@ekleung123 Going to fix that
@jiajinning - ur second return statement doesn't work. Just say "return strs"
@ekleung123 can i only use the replace function for strings?
Hello
function repeat(str, num) {
// repeat after me
if(num<0){
return false;
} else {
var strs = "";
for (var i=0;i<num;i++) {
strs +=str;
}
return strs;
}
// repeat after me
if(num<0){
return false;
} else {
var strs = "";
for (var i=0;i<num;i++) {
strs +=str;
}
return strs;
}
Any ideas on the hangman underscore issue?
@Cal-culator - You can't use the replace method on arrays. Read this: http://www.w3schools.com/jsref/jsref_replace.asp
@ekleung123 thank you
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@ekleung123 then how do i replace in array? I tried assigning but it didn't work
to replace one value over another, you just declare a value over it..for example, let's say your array = ["apple","boy","cat"]
if you want to replace boy with girl, you say array1 = "girl";
it's array[ 1] = "girl"
function titleCase(str) {
var a= str.split(" ");
var b=[];
var c=[];
var d=[];
var e="";
var f=[];
for (var i=0;i<a.length;i++){
b=a[i].split("");
d= c.join("").toUpperCase().split("");
b[0]=d[i];
a[i]= b.join("");
}
a.join(" ");
console.log(a);
}
titleCase("I'm a little tea pot");
you can't join only 1 element in an array
you can say a = b.join("");
What i am trying to do is split the string below into individual words. And then in the loop, split the words into array.
@Cal-culator You might want to
str.toLowerCase().split(" ") (to remove uppercase letters within words), also, you don't return the result of a.join(" ") (it won't change a but return a string, which you currently ignore)
Hello,
I need help in problem 'Sum all Odd Fibonacci Numbers'. I didn't get the idea how to proceed. I need hints.
Thanks
I need help in problem 'Sum all Odd Fibonacci Numbers'. I didn't get the idea how to proceed. I need hints.
Thanks
@Cal-culator I haven't done that exercise you're doing...but what is it supposed to return with titleCase("I'm a little tea pot")
@ekleung123 its supposed to return the first letters of each word upper case
So basically, it should return I'm A Little Tea Pot
Have you tried toLowerCase before splitting into words, and actually returning
a.join(" ")?
@Blauelf Why do i need to lower case? I don't understand
@Cal-culator the input material might be all-caps, and only the first letter should be uppercase.
This message was deleted
@Cal-culator
function titleCase(str) {
var a = str.split(" ");
var b = [];
for (var i=0; i<a.length; i++) {
b.push(a[i].charAt(0).toUpperCase());
}
return b;
}
var y = titleCase("I'm a little tea pot");
console.log(y);
this puts each letter in an array and returns the first letter of each word
@Cal-culator You are doing some odd things with your one-letter variables. I don't really understand why most of them are there. You might be better off giving them meaningful names, like "words" for "a" (it's an array of all the words), "word" or "currentWord" or something like that for "b" (it's an array of the characters in the current word), ...
For example. you call c.join, with c always being the empty array. The result of that line is an array containing a single empty string.
For example. you call c.join, with c always being the empty array. The result of that line is an array containing a single empty string.
@Blauelf Yeah... going to scrap it and start over
how to use images from my google drive in code pen??
haha i misread the assignemnet, i thought it's supposed to only return the first letter in each word
its not much diff to return each word with the first letter capitalzied...i'll work on it now
Can anybody help me with the seek and destroy question? I am stuck as the input is taken as a single array.
@vmohan9 sure, look into arguments
but I do strongly recommend reading the MDN page they link to
yeah I tried that way but it did not pass all the sections... sure I will check on them. What is the use of object in this particular question?
how to use images from my google drive in code pen??
I did not use an object, so I can't say @vmohan9
cool. Thanks @Benalron
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@harryac07 @Blauelf
function destroyer(arr) {
// Remove all the values
var args =arr.slice.call(arguments);
for (var i = 0;i<args.length;i++)
{
if (arr[i] == args[i])
{
return arr;
}
}
}
destroyer([1, 2, 3, 1, 2, 3], 2, 3);
can u guys help
@vmohan9 np, GL
@MohammadHasham Don't randomly tag people.
@Blauelf Apology.
@Blauelf Can you help me with this?
@MohammadHasham try to run through it mentally and see what it would be doing each time
@Benalron I have no clue about this challenge can you help me a lil
@Benalron How can i incorporate the filter?
Mohammad what are you supose to do or return?
@MohammadHasham the first run of the for loop causes the if statement to be, "if 1 == [1, 2, 3, 1, 2, 3]", so that doesnt trigger... the second run through is, if 2 == 2, return arr... so it's returning (ending the entire function, and giving the value of the entire arr)
@MohammadHasham remember, arguments[0] is the array
@Benalron then should i store the value in another variable?
and then return that at the end
@MohammadHasham thats one way to do it that would work... but you don't want to return... return ends the entire function
Yeah you need to make an adfitional if statement that checks if it has more then one value
@Benalron Is it really necesary yo use filter()
@MohammadHasham but youre also checking each argument against only 1 items in the array... you need to make it so you are checking each argument (other than arguments[0], the array] against EVERY number in the array
@Cal-culator
function titleCase(str) {
var a = str.split(" "), b = [];
for (var i=0; i<a.length; i++) {
var x = a[i]
x = x.charAt(0).toUpperCase() + a[i].slice(1,a.length+1);
b.push(x);
}
return b
}
var y = titleCase("I'm a little tea pot");
console.log(y); // yields "I'm A Little Tea Pot"
no... I did it using 2 for loops, @MohammadHasham
If it does than loop through its value or even a good while loop that will loop through every index that has value over 1
@ekleung123 I got it
function titleCase(str) {
var a=str.toLowerCase().split(" ");
var b=[];
var c=[];
var d="";
var e=[];
var f=[];
var g=[];
for (var i=0; i<a.length;i++){
b=a[i].split("");
console.log(b);
c.push(b[0]);
console.log(c);
d = c.join("").toUpperCase();
console.log(d);
e= d.split("");
console.log(e);
b[0]=e[i];
f=b.join("");
console.log(f);
g.push(f);
}
return g.join(" ");
}
titleCase("I'm a little tea pot");
@Cal-culator you dont need to declare so many arrays
@Cal-culator that is a very interesintg solution
@ekleung123 I know. I did it because i was starting to get confused.
i'm not sure that solution would work for every sentence you pass to titleCase
@Cal-culator remember arrays can have arrays inside of them, like, [ [0,1 ], [2,3 ], [3,4 ], [4,5 ], ]
@Cal-culator just try my code .... it does it properly
@Benalron I tried that but it didn't work the way I wanted so I tried a much more simple algorithm
@ekleung123 I did. Its pretty concise. Thanks
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@ekleung123 I didn't know charAt and slice works in JavaScript
@Cal-culator what other langauge do you know?
C++ but haven't used it in a long time so need to refresh
@ekleung123 Java
yeah some of the syntax between java and javascript are similar
@ekleung123 yeah but JavaScript is so much more easier and more user Oriented
I tried java and got lost in it, but guys one question is it realy better than js? I mean can it do something that js cant?
@knox97 Java Script is for browser developing
It can't run on its own while Java can.
It depends on what you are trying to write.
hello everyone, please i want this code to remove the second and third arguments from the first argument which is the array. But it is returning true for every elem, i cant find the bug, or is there a better way to go about it?
function destroyer(arr) {
// Remove all the values
var basearr = arr[0];
var arglength = arguments.length;
var newarray = [];
for (var i = 1; i < arglength; i++) {
newarray.push(arguments[i]);
}
console.log(newarray);
var finalarray = arguments[0].filter(function(elem, index, array) {
elem = false;
for (i = 0; i < newarray.length; i++) {
if (newarray[1] !== elem) {
elem = true;
}
}
return elem;
});
arr = finalarray
return arr;
}
destroyer([1, 2, 3, 1, 2, 3], 2, 3);
I wouldnt agree with that there is nodeJS and it has v8 from google integrated in it @Cal-culator
@Promhize so it it supposed to return [1,2,3,1,2,3]
@Promhize You should try to find an argument equal to elem, and then return false. After loop return true.
supposed to return just [1,1] it is to remove the occurences of 2 and 3 @ekleung123
@Masd925 because the function can except different numbers of arguments, i cant hard code the arguments,so i decided to loop through them first and created an array from them
there seems to be something wrong with the loop, when i remove the loop and pass, newarray[1], it removes all the occurrences of 3
Hello Folks! I'm doing the Profile Lookup Challenge. I want to test it part-by-part, but even when the name is a name in the array, it shows 'No such contact' despite the part about bob having a green tick. How can it be right and wrong at the same time?
//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 (contacts.firstName !== firstName){
return "No such contact";}
}
// Only change code above this line
}
// Change these values to test your function
lookUpProfile("Akira", "likes");
contacts[i].firstName
@kevinstonge Ah, so I have to include the index number to the object access part?
Which API FCC used for sample 'Random Quote Machine' does anyone know?
it's an array of objects in this exercise, so yes.
@kevinstonge Okay. Thank you. It still shows 'No such contact', though. Is that because the task in incomplete?
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show's no such contact for who?
actually... that's poorly written, it will return no such contact the very first time contacts[i].firstName is not the contact name :)
@faisal1337
var args =arr.slice.call(arguments);
function destroyer(arr) {
// Remove all the values
}
function consta(arr)
{
for (var i = 0 ; i<arr.length;i++)
{
if (arr[i] == args[i])
{
}
}
}
destroyer([1, 2, 3, 1, 2, 3], 2, 3);what i need to put in the if conditions in consta()
@leebut You return "No such contact" when there's at least one mismatch, not only if all the names are mismatches.
Meow, Anyone in the mood to explain a bit recursion to me? I seem to be getting wrong idea about how to factorialize a number
@MohammadHasham The var args line has to be inside destroyer, just like your consta function.
I'd switch that to a === and work from there. If it finds a match it should return something (and you'll need to build some conditional statements to return the correct thing)
@voidfire sure, recursion is basically you make a function with a base case that returns stuff, then if that base case isn't met you call the function again inside the function with an altered parameter
@MohammadHasham why would you put them outside destroyer function?
Both args line and the consta should be inside the destroyer.
@Blauelf Then i wont be able to use args in the second function
@faisal1337 Okay i'll try that
@MohammadHasham I told you to put both inside destroyer. If the function is inside the same scope, it can see args.
Put both inside.
And then worry about the condition.
` js
@faisal1337 @Blauelf Okay
@Blauelf can you tell me about the API the sample project used? Random Quote Machine. What's its name?
codePen doesn't ask my location. Why?
$(document).ready(function(){
if (navigator.geolocation) {
navigator.geolocation.getCurrentPosition(function(position){
$("#data").html("a" + position.coords.latitude + "<br>longitude: " + position.coords.longitude);});
};
})
@jamesmillerho try to do it in the FCC editor.
@Blauelf Oh. Thank you. Making my way into the nested array now.
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Do I need to put Javascript code in Codepen in <script> tags or not?
@faisal1337 what is that
@faisal1337 Looked at the source: https://market.mashape.com/andruxnet/random-famous-quotes
@jamesmillerho are you using CodePen to complete the challenge?
And putting the code from Codepen.io to FCC editor?
@faisal1337
function destroyer(arr) {
// Remove all the values
var args =arr.slice.call(arguments);
function consta(args)
{
for (var i = 0 ; i<arr.length;i++)
{
if (arr[i] == args[i])
{
}
}
}
}
destroyer([1, 2, 3, 1, 2, 3], 2, 3);@Blauelf is it okay? and when i am returning anything in consta() it does not return what is the issue here?
@Blauelf thanks.
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@faisal1337 I just type the code on codePen.io
@MohammadHasham You have no return statement, so destroyer implicitly returns
undefined. Also, you never use consta. Oh, and consta would implicitly return undefined in all cases, too.
Put it back in freecodecamp edior.
editor
@Blauelf @faisal1337 Now what should i do?
Now make the condition
use indexOf()
it will help.
@faisal1337 Now the condition would be made in second function?
@MohammadHasham Add return statements to both of your functions, and fix the condition in consta. If you want consta to be used by filter, it should not have a parameter named
args, since this shadows the variable in the outer scope.
@faisal1337 but I am building the weather app so I have to do it on codePen
Hi，everyone. Can you tell me where is my code wrong?
Hi, can you please help me with my code var Bike = function() {
// Only change code below this line.
this.getGear = function(change) {
return change;
};
this.setGear = function(change) {
return change;
};
};
var myCar = new Car();
var myBike = new Bike();
myBike.setGear(4);
@Blauelf Okay i'll try that
function chunk(arr, size) {<br> // Break it up.<br> var arr1 = [];<br> var arr2 = [];<br> for(var i=0; i<arr.length; ){<br> for(var j=0; j<size; j++,i++){<br> arr2[j] = arr[i];<br> }<br> arr1.push(arr2);<br> }<br> return arr1;<br>}<br><br>chunk(["a", "b", "c", "d"], 2);<br>
@jamesmillerho I don't know then. Sorry :/
...sorry
myBike.getGear() should return 4 after calling myBike.setGear(4). and it does not
@hnsxxscyx No HTML here.
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 thecode`.
See also: ☛ How to type Backticks | ☯ Compose Mode | ❄ Gitter Formatting Basics
sorry,How push it?
function chunk(arr, size) {<br> // Break it up.<br> var arr1 = [];<br> var arr2 = [];<br> for(var i=0; i<arr.length; ){<br> for(var j=0; j<size; j++,i++){<br> arr2[j] = arr[i];<br> }<br> arr1.push(arr2);<br> }<br> return arr1;<br>}<br><br>chunk(["a", "b", "c", "d"], 2);<br>
I'm so sorry
@hnsxxscyx u can try putting 3 ticks before and after your codes
`
function chunk(arr, size) {<br> // Break it up.<br> var arr1 = [];<br> var arr2 = [];<br> for(var i=0; i<arr.length; ){<br> for(var j=0; j<size; j++,i++){<br> arr2[j] = arr[i];<br> }<br> arr1.push(arr2);<br> }<br> return arr1;<br>}<br><br>chunk(["a", "b", "c", "d"], 2);<br>
yes,markdown
Now replace the <br> with line breaks (Shift+Return)
BTW, you can edit your posts using the three dot menu that appears when you hover over a post.
BTW, you can edit your posts using the three dot menu that appears when you hover over a post.
@hnsxxscyx 不错嘛
sorry,wait
unction chunk(arr, size) {
// Break it up.
var arr1 = [];
var arr2 = [];
for(var i=0; i<arr.length; ){
for(var j=0; j<size; j++,i++){
arr2[j] = arr[i];
}
arr1.push(arr2);
}
return arr1;
}
chunk(["a", "b", "c", "d"], 2);
:+1:
原来有中国人，救我。。
英语太不行了
耽误大家的时间了，抱歉
@hnsxxscyx You might want to move the var arr2 = []; inside the outer loop, before the inner loop. This way you get a fresh array for each iteration of the outer loop.
And maybe you need a check like j<size && i<arr.length instead of just j<size for not including undefineds when arr.length is not a multiple of size.
Why is not new now? Every '=' didn't cover it?
@faisal1337 @Blauelf
function destroyer(arr) {
// Remove all the values
var args =arr.slice.call(arguments);
function consta()
{
var max = [2,3];
for (var i = 0 ; i<arr.length;i++)
{
if (arr[i] == max[i])
{
return true;
}
}
return false;
}
var new_array ;
for (var i = 0;i<arr.length;i++)
{
new_array= arr.filter(consta);
}
return new_array;
}
destroyer([1, 2, 3, 1, 2, 3], 2, 3);I have harcoded [2,3] in max for the time being later on i'll work on that but why is still it is being tangled?
Ok, I'll try,thanks.@Blauelf
Hello again. Back to the Profile Lookup.
I've got a tick for 'No such property', but I'm having trouble accessing the nested array. I've tried many things, so I'm not being lazy.
I've got a tick for 'No such property', but I'm having trouble accessing the nested array. I've tried many things, so I'm not being lazy.
//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 (contacts[i].firstName !== firstName){
return "No such contact";}
else if (contacts[i] !== prop){
return "No such property";
}
for (var j = 0; j < contacts[i].length; j++){
return contacts[i], [prop][j];
}
}
// Only change code above this line
}
// Change these values to test your function
lookUpProfile("Akira", "likes");
@Blauelf Thanks.
hnsxxscyx sends brownie points to @blauelf :sparkles: :thumbsup: :sparkles:
:star2: 2195 | @blauelf |http://www.freecodecamp.com/blauelf
@hnsxxscyx When pushing arr2 to arr1, you copy a reference to arr2 (or more to the object arr2 is referencing) to the end of arr1. When you change arr2 now, so does the array you just pushed. That's why you should replace the content of arr2 by another empty array.
ok,I know
It's like c, array is a address.
@leebut if you say return "no such contact" when contacts[i].firstName !== firstName ... it will return "no such contact" the very first time it finds an objects in which firstname is not the one passed to it... and since there are four different objects with four different first names; you will almost always get "no such contact" returned. you must begin with === and move from there.
and when it hits "return" the function exits and that value is returned, so anything written after that will not be executed.
@kevinstonge, it's a mess, then.
yeah
@Blauelf
function destroyer(arr) {
// Remove all the values
var args =arr.slice.call(arguments);
function consta()
{
var max = [2,3];
for (var i = 0 ; i<arr.length;i++)
{
if (arr[i] == max[i])
{
return true;
}
}
return false;
}
var new_array ;
for (var i = 0;i<arr.length;i++)
{
new_array= arr.filter(consta);
}
return new_array;
}
destroyer([1, 2, 3, 1, 2, 3], 2, 3);I have hardcoded [2,3] for the time being but i am still left with an empty array when i return new_array? where am i wrong?
@kevinstonge As my code is wrong, the system shouldn't give green ticks to show that part as working.
it's returning the right answer for the wrong reasons :)
@kevinstonge yeah, but that is misleading me. It's not good to learn that way.
@MohammadHasham consta should take one argument, a value, You should then iterate args (ignoring the first element, as this is equal to arr), and compare the args element to the passed value. On match, return false, after the loop return true.
And no need for another loop in destroyer if you are going to use filter.
think of those checkboxes as clues to help you write the algorithm correctly; just because you get a green check mark, doesn't mean your algorithm is any good at all. You need to get them all and understand why you are getting each one.
@Blauelf It's gone,thank you very much.
@kevinstonge I've spent about 40 hours on this JavaScript section. A lot of that is from lack of clarity.
But if I write like this
function chunk(arr, size) {
// Break it up.
var array = [];
for(var i=0; i<arr.length; i++){
array[i] = arr[i];
}
for(i=0,h=0; h<arr.length; i++,h++){
for(var j=0; j<size; j++){
array[i][h] = arr[h];
}
}
//arr = array;
return array;
}
chunk(["a", "b", "c", "d"], 2);
Why "typeError: 0 is read-only"
I have made some changes is that okay ,
@hnsxxscyx Your inner loop does the same thing
size times. Also, you try to access properties of numbers (array contains numbers, you try to use them as arrays)
@Blauelf
function destroyer(arr) {
// Remove all the values
var args =arr.slice.call(arguments);
function consta()
{
var max = [2,3];
for (var i = 0 ; i<arr.length;i++)
{
for (var j=0;j<max.length;j++)
{
if (arr[i] == max[j])
{
return true;
}
}
}
return false;
}
new_array= arr.filter(consta);
return new_array;
}
destroyer([1, 2, 3, 1, 2, 3], 2, 3);
@MohammadHasham Remove that max thing. AND consta SHOULD TAKE AN ARGUMENT. Also, don't loop over arr in consta, but args. And still wrong condition, and true/false inverted.
There's little use in a function passed to filter if it does not take at least one argument.
Filter will call it with three arguments (the current element, its index in the array, and the array itself), and the function will ignore all of them.
For the "Build a Random Quote Machine" challenge, I'm supposed to find my own quote api? why don't they provide one?
Can only guess: Different people might prefer different quotes. And searching for an API that's appropriate and its documentation is a realistic task.
good point :)
i cant access weather icons from google drive what can i do any one help me please
icons extension is ".svg"
icons extension is ".svg"
Is this getting closer to the Profile List?
function lookUpProfile(firstName, prop){
// Only change code below this line
for (i = 0; i < contacts.length; i++){
if (contacts.firstName === firstName){
for (var j = 0; j < contacts[i]; j++){
if (contacts[i] === prop){
return contacts[i][firstName] + contacts[i][prop][j];
}
}
}
}
// Only change code above this line
}
@leebut I don't think you need a j-loop; if firstName you can return contacts[i][prop] or "No such property" ... after the i-loop you can return "no such contact"
Also, it's
contacts[i].firstName, not contacts.firstName
I've taken over two hours doing this challenge. Time for a break. Thank you for helping @Blauelf and @kevinstonge :) I used to think I was a logical person. Obviously not. Time to buy some Spok ears.
leebut sends brownie points to @blauelf and @kevinstonge :sparkles: :thumbsup: :sparkles:
:warning: leebut already gave kevinstonge points
:warning: leebut already gave blauelf points
I'm on the first javascript exercise that uses the map method - "Iterate over arrays with map". I didn't understand how to use that to iterate trough all elements
Just realised how to do that! :)
@faisal1337 What does it mean when indexOf return -1
@Blauelf
How would one use a JS constructor in an ansychronus JSONP api call?
The instance returns permaturely as undefined:
indexOf returns -1 if the element is not found in the array (same goes for string's indexOf, which searches for substrings)
var getResults = function(){
var streamers = ["ESL_SC2", "OgamingSC2", "cretetion", "freecodecamp", "storbeck", "habathcx", "RobotCaleb", "noobs2ninjas"];
$.getJSON('https://api.twitch.tv/kraken/channels/OgamingSC2/?callback=?', function(data1) {
$.getJSON('https://api.twitch.tv/kraken/streams/OgamingSC2/?callback=?',function(data2){
console.log(data1);
console.log(data2);
});
});
}
and the constructor:
function Streamer(resultStream,resultChannel){
this.name = resultChannel.display_name;
this.image = resultChannel.game + ": " + resultChannel.logo;
this.description = resultChannel.status;
this.online = (resultStream.stream != null);
console.log(resultStream);
console.log(resultChannel);
}
This works, but when I use : var streamer = new Streamer(data1,data2); and console.log(streamer); it logs undefined
as if the instance returned earlier than the response : l
Where do you log streamer? Is this after (in time!) the new Streamer? Maybe on the line right after that?
oh sorry I removed that, here you go :smile:
var getResults = function(){
var streamers = ["ESL_SC2", "OgamingSC2", "cretetion", "freecodecamp", "storbeck", "habathcx", "RobotCaleb", "noobs2ninjas"];
$.getJSON('https://api.twitch.tv/kraken/channels/OgamingSC2/?callback=?', function(data1) {
$.getJSON('https://api.twitch.tv/kraken/streams/OgamingSC2/?callback=?',function(data2){
console.log(data1);
console.log(data2);
var streamer = new Streamer(data1,data2);
console.log(streamer);
});
});
}
On "Condense Arrays with reduce" my solution passed the tests, but I'm unsure if this is the "best way" to use the reduce method. What do you think?
var array = [4,5,6,7,8];
var singleVal = 0;
// Only change code below this line.
var singleVal = array.reduce(function(singleVal, el){
return singleVal + el;
});
//singleVal = array;
@victorso I think that's how your supossed to use it , as an accumalator
@Blauelf
function destroyer(arr) {
var args = Array.prototype.slice.call(arguments);
args.splice(0,1);
return arr.filter(consta);
function consta(element)
{
return args.indexOf(element) == -1;
}
}
destroyer([1, 2, 3, 1, 2, 3], 2, 3);How does the return args.indexOf ... is acting ?
@victorso you can also check the wiki
@Blauelf would that not always return false or -1
@MohammadHasham consta returns true if element is not in args, and false if it is (so the result of indexOf is the index, which is >=0)
@Blauelf http://codepen.io/Wo1v3r/pen/BzJbgX?editors=1011 here if youll see on the console, both data1 and data2 log -first- defined and streamer instance logs as undefined
after clicking any of the three buttons atm
@Wo1v3r But why am I defining the accumulator as a separate variable before using the reduce method? Wouldn't that way be better?
var array = [4,5,6,7,8];
//var singleVal = 0;
// Only change code below this line.
var singleVal = array.reduce(function(singleVal, el){
return singleVal + el;
}, 0);
//singleVal = array;
@Blauelf What does the 'element' does in consta it is still the args?
@MohammadHasham element is just an arbitrary name for the array element that filter will pass to the function. As you use
arr.filter, it is an element of arr.
@victorso Well yes , you could also not define it at all because it's defaults @ zero, but they said change only below this line so I guess you have to use it
@Wo1v3r Ok, thanks Jonathan!
victorso sends brownie points to @wo1v3r :sparkles: :thumbsup: :sparkles:
:cookie: 283 | @wo1v3r |http://www.freecodecamp.com/wo1v3r
@Blauelf So how does it know that we need an array and why it has missed the other two elements [2,3]
@victorso That's more exact : 'Note: If initialValue isn't provided, reduce will execute the callback function starting at index 1, skipping the first index. If initialValue is provided, it will start at index 0.' you can shift 0 into the first place
and reduce it so it does 0+4+5... without any other paramaters
or any value @ first index for that matter
function titleCase(str) {
str=str.toLowerCase();
var word;
var i=0;
var position=0;
var np=0;
var long;
word=str.split(' ');
str=str.split('');
str[0]=str[0].toUpperCase();
//return str;
for(i=0;i<30;i++){
long=word[i].length;
np=position+long+1+np;
str[np].toUpperCase();
}
str=str.join();
//return str;
}
Could any one help with the error inside for loop?
the compiler keep saying cannot read property 'toUpperCase' of underfined and cannot read property 'length' of underfined
@Wo1v3r Yeah, nice. There is no need for passing 0 as the second parameter to the reduce method.
@victorso Yup I just think that in most cases you wouldn't use reduce in that way , but that's great to know
hey guys i need your opinion on something, i just skipped the algorithm challenges and data visualisation and went straight to the backend challenges. Bad Idea? or Not?
@Blauelf OK blaeuelf I reduced this problem a bit, if you could check the codepen, creating an instance on the first json callback works, but the problem seems to be with nested getjson, how would i avoid that?
@andrew45655
` ```` ` ```` ` javascript
[code goes here]
` ```` ` ```` `
formats to:
code goes here
@puven12 well keep checking the wiki after you succeeded each challenge and see if there are things used that you completely didn't know about
@victorso Sorry for my reply. Enclose your code between 3 backticks so it has syntax highlight
@Blauelf Thanks
mohammadhasham sends brownie points to @blauelf :sparkles: :thumbsup: :sparkles:
:star2: 2196 | @blauelf |http://www.freecodecamp.com/blauelf
:worried:
@Wo1v3r
function getIndexToIns(arr, num) {
// Find my place in this sorted array.
var x = arr.concat(num);
var c = x.sort();
return c;
//return c.indexOf(num);
}
getIndexToIns([5, 3, 20, 3], 5);why is it not sorting correctly?
@Blauelf
can someone help me out?
@MohammadHasham without a compare function, sort() sorts alphabetically: http://mdn.io/sort
@MohammadHasham ^ :D
Should i use a compare function and return its value would that be enough
more specifically by ascii code so 12 and 8 are read as "12" vs "8" and 1 is lower than 8 so 12 is considered smaller.
yeah if you use a function that returns a comparison of a and b
@Athaman @Wo1v3r @BKinahan Thanks
mohammadhasham sends brownie points to @athaman and @wo1v3r and @bkinahan :sparkles: :thumbsup: :sparkles:
:cookie: 284 | @wo1v3r |http://www.freecodecamp.com/wo1v3r
:cookie: 606 | @athaman |http://www.freecodecamp.com/athaman
:star2: 2003 | @bkinahan |http://www.freecodecamp.com/bkinahan
Completed That!
@Wo1v3r what wiki ?
@puven12 The FCC wiki, when you're on a challenge just click the Wiki in the navbar
@Wo1v3r sure
it will open current challenge's hints and solution, just make sure you understand all the solutions and didn't iss out on anything
@Wo1v3r thanks man. it is very useful
puven12 sends brownie points to @wo1v3r :sparkles: :thumbsup: :sparkles:
:cookie: 285 | @wo1v3r |http://www.freecodecamp.com/wo1v3r
HI! I was reading up documentation on Objects.keys() and dont really understand what it does. What does enumerable properties mean?
Could someone potentially help me figure out what i'm doing wrong?
My code is:
function multiplyAll(arr) {
var product = 1;
// Only change code below this line
for(i = 1; i < arr.length; i++) {
for(n = 1; n < arr[i].length; n++) {
return product * arr[i][n];
}
}
// Only change code above this line
return product;
}
// Modify values below to test your code
multiplyAll([[1,2],[3,4],[5,6,7]]);
When i want to make first letter of each word to upper case, I get error touppercase undefined and 'length' underfined
javascript
[function titleCase(str) {
str=str.toLowerCase(); //lower case all words
var word;
var i=0;
var position=0;
var np=0;
var long;
word=str.split(' '); //split to words
str=str.split(''); //split to letters
str[0]=str[0].toUpperCase(); //upper case the first letter
//return str;
for(i=0;i<30;i++){
long=word[i].length; //get length of words
np=position+long+1+np; //update position of words
str[np].toUpperCase(); //change target word to uppre case
}
str=str.join();
return str;
}]
hello :D so I finished sum all numbers in range yesterday but my code seems ehm too much comlicated for that simple task :D any ideas
function sumAll(arr) {
var min = Math.min.apply(Math,arr);
var max= Math.max.apply(Math,arr);
var number = [];
var final = 0;
for (var i = min+1; i < max; i++) {
number.push(i);
}
var result = number.map(function(bam){
final += bam;
});
return final + max + min;
}
sumAll([5, 10]);
?
@Sleepy-guy Mine was even more complicated
So I think youre good :)
@defeds Youre returning two things currently. Product AND product * arr[i][n]
@JuiceDrinker I get a syntax error if i try to do product * arr[i][n]; :/
Can you repost your code using ```js please?
function multiplyAll(arr) {
var product = 1;
// Only change code below this line
for(i = 1; i < arr.length; i++) {
for(n = 1; n < arr[i].length; n++) {
product = product * arr[i][n];
}
}
// Only change code above this line
return product;
}
@Sleepy-guy since there are only two numbers, you could use
Math.max(arr[0],arr[1]) instead of using apply
One thing to note is that you can write product *= arr[i][n]
@BKinahan
function rot13(str) { // LBH QVQ VG!
var s;
s = str.charCodeAt(0+13);
return str.fromCharCode(s);
}
// Change the inputs below to test
rot13("SERR PBQR PNZC");Why is fromCharCode() giving an error?
@Athaman
@Sleepy-guy there's also a mathematical formula for the sum of numbers in a range if you want something really simple :P
@Sleepy-guy product *= arr[i][n], i get the red X next to my code
dont forget the semicolon
```function multiplyAll(arr) {
var product = 1;
// Only change code below this line
for(i = 1; i < arr.length; i++) {
for(n = 1; n < arr[i].length; n++) {
product * arr[i][n];
}
}
// Only change code above this line
return product;
}
// Modify values below to test your code
multiplyAll([[1,2],[3,4],[5,6,7]]);```
@MohammadHasham
.fromCharCode is called on String, not just any string
woops
also you can hover over the red cross and it will tell you what the problem is
@BKinahan I c.
@defeds It should be *=
@defeds starting at
1 for i and n will cause problems. arrays indices start at 0
@JuiceDrinker oh :D because there is a link with reduce but I dont know hot to use reduce here :D but thanks:D
sleepy-guy sends brownie points to @juicedrinker :sparkles: :thumbsup: :sparkles:
:warning: could not find receiver for juicedrinker
@JuiceDrinker Ohhhhh!
@BKinahan @JuiceDrinker Thank you both so much!
defeds sends brownie points to @bkinahan and @juicedrinker :sparkles: :thumbsup: :sparkles:
:warning: could not find receiver for juicedrinker
:star2: 2004 | @bkinahan |http://www.freecodecamp.com/bkinahan
quick question why doesn't this work? it's a random quote api.
@BKinahan, What does enumerable properties mean?
$.getJSON("http://quotes.stormconsultancy.co.uk/random.json?callback=?", function(data) {
console.log(data);
});
Can someone tell me why 'streamer' logs as undefined ? :( http://codepen.io/Wo1v3r/pen/BzJbgX?editors=0111
@BKinahan yea I really didn't know how to use that math max because it didn't work properly on array :D
@JuiceDrinker there are some great answers about that here: http://stackoverflow.com/questions/17893718/what-does-enumerable-mean
$(document).ready(function(){
if (navigator.geolocation) {
navigator.geolocation.getCurrentPosition(function(position){
$.getJSON('http://api.openweathermap.org/data/2.5/weather?lat='+position.coords.latitude+'&lon='+position.coords.longitude+'&appid=833dc2ccd1bb85729f4b968468cc1ad5', function(json){
$("#data").html(JSON.stringify(json))});
});
};
})^
the api content doesn't display on the page
@robertx32 Are you in https or http codepen?
@Sleepy-guy you can use the new ES6 spread operator for that!
Math.max(...arr)
no http at all,
@robertx32 it works on my end, use this: codepen.io/Treborx555/pen/xOpvkW?editors=0002
i get this in the console
Object {
author: "E. W. Dijkstra",
id: 15,
permalink: "http://quotes.stormconsultancy.co.uk/quotes/15",
quote: "It is practically impossible to teach good programming style to students that have had prior exposure to BASIC. As potential programmers, they are mentally mutilated beyond hope of regeneration."
}
theres a problem with your button though
but the getson works
thanks, will check
How about this
All.good?
wow it works, did you change anything?
such concise code :P
Well I did a quick Google and it turns out
I needed to use
Something along the lines of
Kinda lkke
With the jist of
gitter does allow messages that are longer than a handful of words, by the way.
Um quite
No
It
Doesn't
O
N
L
Y
[space]
A
[space]
S
I
N
G
L
E
[space]
E
L
T
T
E
R
LimpingLlama @LimpingLlama doesn't understand life