Issue 1168: Matrix([[x+y, -x, 0], [-x-y, x, 1], [0,1,0]]).inf() gives wrong
result
http://code.google.com/p/sympy/issues/detail?id=1168
New issue report by ondrej.certik:
In [1]: A = Matrix([[x+y, -x, 0], [-x-y, x, 1], [0,1,0]])
In [2]: Ainv = A.inv("ADJ")
In [3]: Ainv
Out[3]:
⎡ -1 -x
Updates:
Status: Fixed
Comment #7 on issue 1168 by smi...@gmail.com: Matrix([[x+y, -x, 0], [-x-y,
x, 1], [0,1,0]]).inf() gives wrong result
http://code.google.com/p/sympy/issues/detail?id=1168
regarding subs of oo: since -oo is a singleton, it is missed by the current
logic of subs.
Comment #2 on issue 1168 by sherjilo...@gmail.com: Matrix([[x+y, -x, 0],
[-x-y, x, 1], [0,1,0]]).inf() gives wrong result
http://code.google.com/p/sympy/issues/detail?id=1168
THis problem doesn't come up in my version of SymPy. I think this issue has
been fixed and needs to be closed.
--
Comment #3 on issue 1168 by asmeurer: Matrix([[x+y, -x, 0], [-x-y, x, 1],
[0,1,0]]).inf() gives wrong result
http://code.google.com/p/sympy/issues/detail?id=1168
I get
print Matrix([[x+y, -x, 0], [-x-y, x, 1],
[0,1,0]]).inv().applyfunc(simplify)
[ (oo)*x**4*
Comment #4 on issue 1168 by sherjilo...@gmail.com: Matrix([[x+y, -x, 0],
[-x-y, x, 1], [0,1,0]]).inf() gives wrong result
http://code.google.com/p/sympy/issues/detail?id=1168
This is more of a simplify problem, than a matrices problem. The LU and GE
methods aren't as symbolically stable as
Comment #5 on issue 1168 by asmeurer: Matrix([[x+y, -x, 0], [-x-y, x, 1],
[0,1,0]]).inf() gives wrong result
http://code.google.com/p/sympy/issues/detail?id=1168
simplify() can slow things down quite a bit, so we do not call it by
default, even in methods like rref() where the correctness c
Comment #6 on issue 1168 by sherjilo...@gmail.com: Matrix([[x+y, -x, 0],
[-x-y, x, 1], [0,1,0]]).inf() gives wrong result
http://code.google.com/p/sympy/issues/detail?id=1168
subs(oo, 100) doesn't substitute all the infinities. Why is that so ? If it
would have worked, we could have such an
