sympy/sympy — pull request #8701 by shivamvats (2014-12-27 10:44:30+00:00)
Title: Modified default range to interpret the assumptions of free_vars

Currently plot has a default range of (-10,10) when user doesn't
provide a range. However this default behaviour doesn't care about the
properties/assumptions of the free_variables. This commit corrects
this situation for two such cases, ie, when the variable is positive
and when it is negative.