Kate MacInnis wrote: ... > Another unexpected one was this: > In [6]: (((x**2*y**4)**a)**(x*y))**3 > Out[6]: > 3 > ⎛ x⋅y⎞ > ⎜⎛ a⎞ ⎟ > ⎜⎜⎛ 2 4⎞ ⎟ ⎟ > ⎝⎝⎝x ⋅y ⎠ ⎠ ⎠ > > In [7]: powdenest(_) > Out[7]: > 6⋅a⋅x⋅y > ⎛ 2⎞ > ⎝x⋅y ⎠ > > instead of the > 3⋅a⋅x⋅y > ⎛ 2 4⎞ > ⎝x ⋅y ⎠ > that the test wants. Is there some reason that the two wasn't > supposed to be pulled out?
Yes...`(x**2)**y != x**(2*y)` unless x is nonnegative, e.g. `((-1)**2)**(1/2)` = 1 but `(-1)**(1) = -1` polys12 is giving this result, too. I'm not sure why it and your work allows this to not work. I successfully tracked this power rules bug (which is lurking in several places) in my t2 branch (which also has the expand re-write) but master changed so much underneath it before portions were reviewed that it is difficuly to rebase on master. I am rebuilding it a commit at a time. I would recommend just XFAILing this test and when t2 is finally merged this problem will be resolved. I would not recommend trying to track this bug down as it is independent of your current quest. /c -- You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
