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##### Activity
• Sep 12 2022 01:39

• Sep 11 2022 12:19

Implemented leading term and ns… (compare)

• Sep 10 2022 03:21

• Sep 08 2022 06:28

• Sep 08 2022 03:43

Changed the outputs being retur… (compare)

• Sep 07 2022 09:34

Changed leading term being ret… (compare)

• Sep 07 2022 07:27

Removed Redundant block from le… (compare)

• Sep 07 2022 02:44

anutosh491 on GSoC_Pr4.3_Implementing_some_series_method_for_uppergamma_lowergamma_expint_and_other_errors_functions

Implemented some series methods… (compare)

• Sep 06 2022 16:44

Removed Order term (compare)

• Sep 06 2022 11:39

added test cases for limits and… (compare)

• Sep 06 2022 10:51

Implemented leading term and ns… (compare)

• Sep 06 2022 10:40

anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions

• Sep 06 2022 04:13

anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions

This commit does the following … Refactored mrv_leadterm in grun… Fixed errors arising for limits… and 3 more (compare)

• Sep 06 2022 02:08

anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions

fix(integrals): handle degenera… functions: Generalised Dirichle… author: update Megan Ly in .mai… and 23 more (compare)

• Sep 05 2022 14:16

anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions

Changed if condition for bessel… (compare)

• Sep 05 2022 02:49

anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions

Improved code quality (compare)

• Sep 03 2022 10:24

anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions

changed is function to equality… (compare)

• Sep 03 2022 10:14

anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions

fixed failing tests (compare)

• Sep 01 2022 12:23

anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions

Fixed code quality (compare)

• Sep 01 2022 12:00

anutosh491 on GSoC_Pr4.1_Implementing_few_series_methods_for_bessel_functions

Added case where number of term… (compare)

kirk86
@kirk86
How should I be reading the first case? Where does the scalar 0.07... comes from? What the meaning for arg() function?
for E[X*Y] = E[X]*E[Y] I was expecting E[X]=0.1 then E[X]*E[Y] = 0.1*pdf(Y) which is closer the otherwise case represented in the screen shot above, without the 0.07..., scalar which haven't figured out where it came from?
Aaron Meurer
@asmeurer
0.07071... is 0.1*sqrt(2)/2. If you call simplify(E(X*Y)).evalf() it will evaluate the floats.
The arg is the complex argument. If you set symbols('mu sigma', real=True) it will assume the arguments are real and simplify
kirk86
@kirk86
@asmeurer thanks a lot, that makes sense now! It seems that sometimes is evalf() and others just evaluating using some argument stats.density(X)(x). Another issue that seems common is the sympy console after activation sympy.init_session() throws an error whenever using the python function locals(). Also, in sympy console executing sympy.stats.Normal(...) doesn't recognise the submodule stats, one has to separately import each submodule. Are there any ways to overcome these issues? Thanks!
krishna
@Krishnacse20
Hello " Sympy " world ,I am newbie here and now i am going to start contribution to this organization .if possible , can you guys tell me , from where to start ???
JSS95
@JSS95
@asmeurer, will you please take a look at the discussion in #20475 and participate?
James Hill
@James-G-Hill
Equivalent(
Interval(b - epsilon, b + epsilon, True, True),
ConditionSet(y, Abs(y - b) < epsilon, Reals)
)
Anyone willing to help me understand why this doesn't return a boolean True? Are there steps that I'm missing?
I'm a sympy learner & trying out lots of the modules. Would like to contribute at some point but still got a lot to learn.
Ori Lahav
@vbCrLf

Hey, I'm new to Sympy.

I'm trying to find a minimum to a function under some constraints. The function has two variables: x,y, and two parameters: l < 0 and u > 0.
The function is:
0.5*u**2 - 1.0*y**2/(1 - x)**2 + 1.0*y*(y/(1 - x) + y/x)/(1 - x) + 0.5*(-l - y/x)*(-l*x - y) - 0.5*(u + y/x)*(u*x + y)
and the constraints are:
(y >= 1.0e-6) & (l*x + y <= 1.0e-6) & (u*x + y <= u + 1.0e-6)

(l,u parameters == are known at the time of solving. I have to find x,y which gives a minimum given some l,u assignments)

What is the best approach to solve it? Should I use Sympy or other tools?
Thanks!

Ori Lahav
@vbCrLf
rsb11
@rsb11
Hello Everyone, Iam a fourth year engineering student pursuing B. Tech . I have a interest in mathematics as well as python. I want to learn more about new things. Also , i want to contribute to the open source projects. If anyone can help, That would be great help.
Hardik Katehara
@hardikkat24
Hello everyone, I am a Sophomore at BITS Pilani pursuing B.E. in Computer Science. I have decent understanding of python. I am interested in Mathematics. I am new to open source and SymPy. I need help in finding my first issue.
kirk86
@kirk86

Could someone point out what I'm missing here:

X = stats.Exponential('x', 1)
a = sympy.symbols('a', positive=True)
stats.P(X >= a).simplify()

it throws an attribute error:
AttributeError: 'Intersection' object has no attribute 'as_coeff_Mul'

Aaron Meurer
@asmeurer
Probably a bug. Can you open an issue for it
Calvin Winkowski
@telnoratti
I'm working with generating functions in sympy and trying to improve performance by adding O(x**N) in various places. I'm seeing pretty surprising results, for example (Sum(5*6**(-n)*x**n/2, (n, 1, 10)) + Rational("1/2") + O(x**11)).doit() takes way longer than (Sum(5*6**(-n)*x**n/2, (n, 1, 10)).doit() + Rational("1/2") + O(x**11)).doit(). The difference is the doit() on the Sum before adding the order term. I'm also seeing some oddities when raising a polynomial with an order term to a power. Is there any guidance or something I can read to understand what's going on here and how to use order terms to be efficient?
Aaron Meurer
@asmeurer
I don't think Sum knows about order terms. It just evaluates the sum then the order removes the higher order terms.
You might try using the series() method rather than using an order term, although both should work.
Calvin Winkowski
@telnoratti
Thanks, I'll try it out
Calvin Winkowski
@telnoratti
Looks like the series method is for getting a series expansion of a function. I'm calculating my coefficients directly from a recurrence relation. I'm not sure I could easily come up with a function whose expansion would match what I'm looking for. I think I got my issue sorted by using doit() on my Sums and instead of raising my polynomials to a power, doing a for loop with p_n = expand(p_n * p_1). It's not elegant, but it completes in seconds rather than OOMing my machine after several minutes. I'd guess the order term is evaluated at the end of raising something to the nth term.
Aaron Meurer
@asmeurer
the order term is probably causing things to truncate at each intermediate step. The series method should be smarter about how to expand an expression to only the given terms globally, whereas Order is likely to act greedily and not necessarily in the most efficient way.
Could anyone explain the check named "continuous-integration/travis-ci/pr" ? And what should be done to pass those tests ? (Does it take long enough to pass that test?)
Aaron Meurer
@asmeurer
We are in the process of moving from Travis to GitHub Actions. For now, Travis may take a while to complete.
5 replies
Venkatesh B H
@VenkateshBH99
Hi, devs!
This is Venkatesh from India and I’m a Computer student. I have a good grip on python .I have a few things that I’d like to improve and I need to know where can I discuss. Looking forward to contribute.
Vishesh Mangla
@Teut2711
phi0, phi1 = sm.symbols("phi_0 phi_1")
eta1 = 3/phi0**2 * (phi0*sm.coth(phi0) - 1)
eta2 = 3/phi1**2 * (phi1*sm.coth(phi1) - 1)
sm.nonlinsolve([3/15 - eta1/eta2,phi0 - 10*phi1], [phi0, phi1])
gives $\left\{\left( 10 \phi_{1}, \ \phi_{1}\right)\right\}$ . But its obvious that I need the solutions. Plz help
@utkarsh-ls
Hello !!
I am Utkarsh Upadhyay, and I am currently a second-year Computer Science Undergraduate at IIIT Hyderabad. I want to make contributions to this organization and would love to continue contributing for GSoC 2021. I would request the mentors and experienced developers to please guide me throughout the process.
Thanks
Aaron Meurer
@asmeurer
@XtremeGood it looks like a bug that it gives that
I don't know if this equation can be solved in closed form. You can try substituting phi0 for 10*phi1 in the first equation.
But even then, solve() can't solve it.
There might be a solution in terms of LambertW, but if there is, solve() doesn't know how to find it, even after rewriting the equation in terms of exp
Vishesh Mangla
@Teut2711
@asmeurer I would be happy with a numerical solution. I currently am using scipy.optimize.fsolve but I have to rewrite the equation every time. Sometimes I' m given eta and sometimes phi. With symbolic computation I could have prevented typing the expression and and given two values of phi and an eta, I could have found the eta at another fi and vice versa for two values of eta and a phi.
Taichen Rose
@willsower
Hello! I was wondering if anyone could lead me to where I can learn more about Sympy objects (performing research to see if one can pry apart a SymPy object) , or it's data structure. I've looked a lot at the documentation and wiki, but there seems to be a lot of 'how-tos' and not necessarily information about the objects themselves. Thanks in advance!
ABKor752
@ABKor752
How does print() work on matrices in sympy?
somanbhoyar
@somanbhoyar
hello! I want to know how to install Sympy from git. I am looking forward to contributing . please guide me
Akshat Sood
@akshatsood2249
Can someone please tell where can I find source code for Sympy Website?
Naveen Sai
@naveensaigit
Aaron Meurer
@asmeurer
@XtremeGood you should probably use SymPy to compute the intermediate function and then convert it with lambdify to something you can send to fsolve
Aaron Meurer
@asmeurer
Or sympy.nsolve if you want to get a numeric solution with SymPy.
ABKor752
@ABKor752
Could someone help me understand the syntax behind this test case in test_coordsysrect.py (vector module)?
I'm primarily confused by the backslash then indent
*newline
Ansh Mishra
@theanshm
the "\ " is used so that long lines of code can be continued on the next line. This is to improve readability and follow pep8 style. It allows us to open multiple files at once in the code editor without needing to scroll to read the full line of code.
Eva Tiwari
@evatiwari
Hello, I had a couple of doubts, they might seem a bit basic:
I want to import euler's constant (e) in a file in one of the modules. Can someone help me out with it?
Also, I made some changes to my clone of sympy, and i wanted to import this clone as a library and write some code with it (to test the changes). How should I proceed?
I need to use my clone as a library as I am getting an assertion error for changes made in the function, and I have no clue what is the actual output given by the new function.
Kalevi Suominen
@jksuom
From the docstring of Exp1:
    The transcendental number e = 2.718281828\ldots is the base of the
natural logarithm and of the exponential function, e = \exp(1).
Sometimes called Euler's number or Napier's constant.

Exp1 is a singleton, and can be accessed by S.Exp1,
or can be imported as E.

Examples
========

>>> from sympy import exp, log, E
>>> E is exp(1)
True
>>> log(E)
1
Eva Tiwari
@evatiwari
Ok so in that file, E has been imported as the function to calculate expected value (stats module). But this gave me a hint anyway, I'll use exp(1) instead. Thanks a lot!
If someone could help me out with the second doubt, that would be great.