Re: Issue 2169 in sympy: using as_two_args identifies error in fraction

2011-01-30 Thread sympy
Comment #1 on issue 2169 by smi...@gmail.com: using as_two_args identifies error in fraction http://code.google.com/p/sympy/issues/detail?id=2169 _new_rawargs should really re-compute the commutivity of the expression as it is possible that all the passed arguments are commutative. This is

Re: Issue 2081 in sympy: Pow substitution introduces wrong answers

2011-01-30 Thread sympy
Comment #12 on issue 2081 by smi...@gmail.com: Pow substitution introduces wrong answers http://code.google.com/p/sympy/issues/detail?id=2081 This substitution is already prohibited in my t2 branch...from which portions are in review. h[1] >>> (x**3).subs(x**2,Symbol('y')) x**3

Re: Issue 2081 in sympy: Pow substitution introduces wrong answers

2011-01-30 Thread sympy
Comment #13 on issue 2081 by asmeurer: Pow substitution introduces wrong answers http://code.google.com/p/sympy/issues/detail?id=2081 How does it work for exp? I don't think prohibiting it will work because there are some places that require it to work (create the fractional exponent), and

Issue 2172 in sympy: diagonalize method to Matrix

2011-01-30 Thread sympy
Status: Accepted Owner: asmeurer Labels: Type-Enhancement Priority-Medium EasyToFix Matrices New issue 2172 by asmeurer: diagonalize method to Matrix http://code.google.com/p/sympy/issues/detail?id=2172 Matrix doesn't seem to have a diagonalize method, to compute the diagonalization (see htt

Re: Issue 2081 in sympy: Pow substitution introduces wrong answers

2011-01-30 Thread sympy
Comment #14 on issue 2081 by smi...@gmail.com: Pow substitution introduces wrong answers http://code.google.com/p/sympy/issues/detail?id=2081 All the tests pass there. But it seems that exp should never be invalid b/c the base is positive so exp(x)**y = exp(x*y) = exp(y)**x. -- You receiv

Re: Issue 2081 in sympy: Pow substitution introduces wrong answers

2011-01-30 Thread sympy
Comment #15 on issue 2081 by smi...@gmail.com: Pow substitution introduces wrong answers http://code.google.com/p/sympy/issues/detail?id=2081 But t2 also support algebraic subs: h[3] >>> exp(x**3).subs(x, Eq(x**2, y)) exp(y**(3/2)) Here, you are saying "replace x with the first solu

Issue 2173 in sympy: limit(tan(x)**(-1/x),x,0) generates infinite recursion

2011-01-30 Thread sympy
Status: Accepted Owner: smi...@gmail.com Labels: Type-Defect Priority-Medium Series New issue 2173 by smi...@gmail.com: limit(tan(x)**(-1/x),x,0) generates infinite recursion http://code.google.com/p/sympy/issues/detail?id=2173 This expression generates and infinite recursion error, repeating

Re: Issue 2173 in sympy: limit(tan(x)**(-1/x),x,0) generates infinite recursion

2011-01-30 Thread sympy
Updates: Labels: smichr NeedsReview Comment #1 on issue 2173 by smi...@gmail.com: limit(tan(x)**(-1/x),x,0) generates infinite recursion http://code.google.com/p/sympy/issues/detail?id=2173 2173: tan and cot leading terms fixed The leading term for tan and cot were being