Status: Valid
Owner: ----
Labels: Type-Defect Priority-Medium
New issue 3720 by [email protected]: powsimp should be attempted for
multiple generators case in solve
http://code.google.com/p/sympy/issues/detail?id=3720
var('a,b,c,d',positive=True)
(a, b, c, d)
solve(a*b**x-c*d**x, x)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "sympy\solvers\solvers.py", line 826, in solve
solution = _solve(f[0], *symbols, **flags)
File "sympy\solvers\solvers.py", line 1333, in _solve
"\nNo algorithms are implemented to solve equation %s" % f)
NotImplementedError: multiple generators [b**x, d**x]
No algorithms are implemented to solve equation b**x
But solve does know how to solve this:
solve(b**x-a/c,x)
[(log(a) - log(c))/log(b)]
And powsimp can reduce the ratio of powers to a single power:
powsimp(b**(-x)*d**x)
(d/b)**x
So a solution should be possible. But the algorithm doesn't leave the power
together:
solve(_-a/c,x)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "sympy\solvers\solvers.py", line 826, in solve
solution = _solve(f[0], *symbols, **flags)
File "sympy\solvers\solvers.py", line 1333, in _solve
"\nNo algorithms are implemented to solve equation %s" % f)
NotImplementedError: multiple generators [b**x, d**x]
No algorithms are implemented to solve equation b**x
--
You received this message because this project is configured to send all
issue notifications to this address.
You may adjust your notification preferences at:
https://code.google.com/hosting/settings
--
You received this message because you are subscribed to the Google Groups
"sympy-issues" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at http://groups.google.com/group/sympy-issues?hl=en.
For more options, visit https://groups.google.com/groups/opt_out.
