- Join over
**1.5M+ people** - Join over
**100K+ communities** - Free
**without limits** - Create
**your own community**

- 06:44COOLIRON2311 commented #17901
- 06:40COOLIRON2311 commented #17901
- 06:21COOLIRON2311 edited #17901
- 05:55COOLIRON2311 edited #17901
- 05:54proy87 opened #17909
- 04:28smichr edited #17893
- 01:31codecov[bot] commented #17908
- 01:30codecov[bot] commented #17908
- 00:20asmeurer commented #17908
- Nov 14 23:59sympy-bot commented #17908
- Nov 14 23:59asmeurer opened #17908
- Nov 14 21:07molysgaard commented #17790
- Nov 14 19:49nishantwrp starred sympy/sympy
- Nov 14 18:45asmeurer commented #17841
- Nov 14 18:30asmeurer commented #17901
- Nov 14 18:26asmeurer commented #17895
- Nov 14 18:25photonlines starred sympy/sympy
- Nov 14 18:04jksuom commented #17907
- Nov 14 18:02drewsynan starred sympy/sympy
- Nov 14 17:59Dr-G commented #17895

@valglad Amazing! I will test.

There are 6 rows and only 5 columns. One row could be omitted.

I have created

`mrationalize = lambda x: [nsimplify(e) for e in [r for r in x]]`

that I do not like much the fell.
I have a problem with calculating eigenvectors for a simple 3x3 matrix in sympy. Trying to execute

```
q = symbols("q", positive=True)
m = Matrix([[-2, exp(-q), 1], [exp(q), -2, 1], [1, 1, -2]])
#m.eigenvects(simplify=True)
m.eigenvals()
```

results in very complicated expressions for the eigenvalues, trying to get the eigenvectors fails with a NotImplementedError. I expect the latter to be due to the former. However, when trying to do the same thing in Mathematica, I get much simpler expressions for everything. Is there some option / flag that I can set to have sympy compute these eigenvalues and eigenvectors? Is there currently some form of limitation within sympy that prevents me from doing this?

@adoa does Mathematica give a simpler expression for the eigenvalues?

Oh apparently they can be simplified if you call

`simplify`

@adoa it seems there is a

`simplify`

flag, but it doesn't work
This may help you

You should use whichever you feel more comfortable with

(sorry for these silly questions... I am trying my best ,i just need some guidance )

I guess it's because

`Add`

does the smart substitution but `Symbol`

does not
The cosine is irrelevant. It's the same with

`x.subs(x - 1, y)`

vs. `(x + 1).subs(x - 1, y)`

So

`Symbol._eval_subs`

should do the same thing as `Add._eval_subs`

.
@asmeurer: I am somewhat confused regarding the simplification. Apparently there is a difference between

`simplify(a_list)`

and `[simplify(element) for element in a_list]`

. With the latter, I get the same expressions as in Mathematica, the former does not simplify at all o_O. In any case: thanks for opening the issue :-)
It's a bit unclear in the docstring. I take it they are being represented as radius vectors from the origin along the major & minor axis ?

I have some basic level knowledge in Python, FLINT, NumPy

@akshit1511 Hi, i am also new, i'll tell you what i'll be doing to get started, first of all i'll learn to use git and github and then https://github.com/sympy/sympy/wiki has a lot of information on how to start

@akshit1511 Tell me if i am missing something.