On Mar 21, 12:06 pm, Alastair Irving <alastair.irv...@sjc.ox.ac.uk> wrote: > HI All > > I'm running Sage 4.6.2. I've just noticed that if I evaluate various > symbolic expressions which return 0 then the 0 returned is a python int, > rather than a Sage integer. examples of such expressions are sin(0), > tan(0), ln(0). > > Is there a reason for this or is it a bug? >
I would consider this a bug, but because it should return a symbolic expression. sage: a = sin(pi) sage: a 0 sage: type(a) <type 'sage.symbolic.expression.Expression'> It's possible to get this behavior: sage: type(sin(0,hold=True).simplify()) <type 'sage.symbolic.expression.Expression'> Anyway, this is an oversight, I would say. Anyone else care to comment? Otherwise it would be great if you'd file a bug report. This is important to fix, because some Sage code depends on the input in integer form being Sage integer or something else with Sage methods, not a Python int, and one could imagine someone relying on this and getting a nasty exception. By the way, I hope you aren't getting 0 for ln(0)! sage: ln(0) -Infinity - kcrisman -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
