A computer algebra system written in pure Python http://sympy.org/ . To get started to with contributing https://github.com/sympy/sympy/wiki/Introduction-to-contributing
In Mathematica, I'd match a pattern like f_[x]
sympify('f(x)').match(Function(Wild('g'))(Symbol('x')))
(Stripping the commutative assumption off of the Wild symbol doesn't do the trick....)
F_x = Wild('F', properties=[lambda e: e.args == (x,)])
https://github.com/sympy/sympy/wiki/Introduction-to-contributing has some pointers to help get you started
Hello ,I am trying to approach couple of issues involving Sum.doit() but I am not able to understand completely how doit works for a Sum/Integral ( sometimes the recursive call and other times the not so self-explanatory variables like 'rep','did' etc (yeah i know its not possible to write self-explanatory variables always) in the code throw me off and finding it a bit tough to relate as a whole .
any guidance by someone familiar with doit/concrete module regarding how does doit calculate a basic sum like an infinite geometric series would be great ! Thanks
Just wanted to point out that I wrote some ideas/examples in https://github.com/sympy/sympy/discussions/22219 looking forward to any feedback
I think that I found a bug on the evaluation of the limits of a function that I summarize in this pic. Any tips? I can also provide the code to reproduce it.
Of course L and r are symbols positive defined
The limit is different in the discontinuity points.
I am looking to setup a workflow to work on a pull request. In particular, I am looking for some way to be able to edit the library and then immediately check manually/interactively if I obtained the intended result. For example, to have a conda environment which uses the fork as the source for sympy. Any ideas? I have read through the development workflow document, but I feel I'm missing the point on how to do this effectively.
Hi, is sympy 1.9 officially released? I saw it is tagged on github, but the usual files for downloading are missing and pypi also only lists 1.9cr1 as latest version. The sympy.org website is also not helpful in this regard, showing the release of 1.7.1 as latest news.
Hi guys , I was solving an issue regarding functions/limits and I came across something which might help . So do we have any method /function in sympy that checks whether some function/expression might encapsulate or bound another expression . Like is there any way I could check something like -1/x < cos(x)/x < 1/x or even one sided
Hi, it seems that the
.subs function is quite slow. When I have a long expression e (can contain nonlinear terms like x**2, y*x*z), calling e.subs(some_dict) takes quite sometime (a sec or so). In fact subs is often slower than solving for large equations. Am I using subs correctly?
hi guys i'm new with sympy, so can anyone help me with solving this problem?
I was trying it on my own, but i can't get a grip on how to solve this Error
import sympy as sp
from sympy import exp, oo
sp.init_printing()
x = sp.Symbol("x")
a, m, h = sp.symbols("a, m, h", positive = True)
A = sp.Symbol("A")
f = exp(-2 * a * m * x**2 / h)
int_f = sp.integrate(f, (x, 0, oo))
eq1 = 2 * (abs(A))**2 * (int_f) - 1
print(sp.solve(eq1, A))
wow it works thank u!!!!
Hello all. Henry here , I'm using sympy for the first time for one of my course project reports at my University. The course is based on series and summations overall and while trying to get familiar I realized that
Sum((-1)**(x+1) + (-1)**(x+2) , (x, 1, oo)).is_convergent() is not returning the expected result and raises a TypeError saying Invalid NaN comparison , is this a meaningful error or Am I missing something useful ?Maybe I could raise an issue ?
Try:
sym.simplify(sym.Sum((-1)**(x+1)+(-1)**(x+2),(x,1,sym.oo)))
So basically try to simplify the expression, may yield some more insight also in other cases.
@Henrysm41987301_twitter hey Thanks for pointing this out . No need to raise an issue ,there is a fix for similar errors in sympy/sympy#22200 which is currently being reviewed by @oscargus and others .Maybe after that is fixed you could use this expression!
1 reply
When we create an undefined function using Function(name), it is possible to add attributes to it using kwargs, e.g. F=Function('F', foo=bar), which will expose F.foo, as well as consider it a different function if foo is not the same. I'm looking for similar behaviour when subclassing Function, is there a way to do so?
It might help if you create the symbol with the same assumptions as whatever you are substituting