Comment #4 on issue 1515 by kevingoo...@gmail.com: caching does not distinct ints and longs http://code.google.com/p/sympy/issues/detail?id=1515
This boils down to two issues, neither of which is actually a caching problem: 1) Integer instances can be created with an inappropriate internal representation. For example, a long may be used for small integers like 3, or oddly-behaving types like numpy.int32 might be used. The fact that these broken instances get cached and reused exasperates the problem, but is not fundamentally wrong. The patch I submitted in issue 1458 addresses this, but there are some outstanding issues. 2) The matrix code is extremely picky about the types it accepts. Looking at the code it seems this extends well beyond refusing to use a long for a dimension. This is a problem for compatibility with packages like numpy, and it violates users' expectations by not adhering to Python's duck-typing philosophy. I imagine all that explicit type checking produces a performance hit as well. -- You received this message because you are listed in the owner or CC fields of this issue, or because you starred this issue. You may adjust your issue notification preferences at: http://code.google.com/hosting/settings --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sympy-issues" group. To post to this group, send email to sympy-issues@googlegroups.com To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en -~----------~----~----~----~------~----~------~--~---
