[with patch and package] bug in symbolic arithmetic with exp

[burcin]

sage: var('kappa')
kappa
sage: x = sqrt(kappa)
sage: F = exp(x)
sage: F
e^sqrt(kappa)
sage: F/F
e^(2*sqrt(kappa))
sage: 1/F
e^(-sqrt(kappa))
sage: (1/F) * F
e^(2*sqrt(kappa))

CC: @jasongrout

Component: symbolics

Author: Burcin Erocal

Reviewer: Nick Alexander

Merged: 4.0.2.alpha0

Issue created by migration from https://trac.sagemath.org/ticket/6256

[burcin]

comment:1

Here is the fix for pynac:

diff --git a/ginac/mul.cpp b/ginac/mul.cpp
--- a/ginac/mul.cpp
+++ b/ginac/mul.cpp
@@ -1167,7 +1167,7 @@
        if (cmpval != 0) {
                return cmpval;
        }
-       if (seq.size() == 1 && overall_coeff.is_equal(_ex_1))
+       if (seq.size() == 1 && overall_coeff.is_equal(_ex1))
                return 0;
        return 1;
 }

I'll post an updated spkg later together with a fix for #6244.

[burcin]

Attachment: trac_6256-pynac_mul_compare_tests.patch.gz

doctests

[burcin]

comment:2

New pynac package fixes this:

http://sage.math.washington.edu/home/burcin/pynac/pynac-0.1.8.p0.spkg

It also contains fixes for #6244 and #6211, so doctests should be run with patches from those tickets applied.

Jason, can you review this?

[ncalexan]

Reviewer: Nick Alexander

[ncalexan]

comment:3

Fine by me, works with new spkg.

[ncalexan]

Merged: 4.0.2.alpha0

[ncalexan]

Author: Burcin Erocal