From: SourceForge.net <noreply@so...>  20040224 03:25:57

Bugs item #903190, was opened at 20040223 22:15 Message generated for change (Tracker Item Submitted) made by Item Submitter You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=903190&group_id=4933 Category: None Group: None Status: Open Resolution: None Priority: 5 Submitted By: Stavros Macrakis (macrakis) Assigned to: Nobody/Anonymous (nobody) Summary: sin(%pi+%pi*x) doesn't simplify Initial Comment: sin(%pi+%pi*x) doesn't simplify (cf 580721) ...similarly for other trig functions. The problem is that the %piargs code only looks for xxx+k*%pi/2 where xxx is %pifree. Even sin(f(%pi)+%pi) doesn't simplify! There are two main ways to try to fix this: 1) *Add* a purely syntactic check before or after the existing semantic check. This is appealing because a) it will clearly work and b) it can't screw up the form of the expression. 2) Replace the current semantic check with one which looks for a k*%pi/2 term among other terms. For example, sin((%pi+1)^3) has a 12*%pi term, so could simplify to sin(%pi^3+6*%pi^2+8). But is that really useful? I don't think so, and if the user wanted it with the syntactic approach, s/he could just use expand. Even less useful would be sin((%pi+1)^312*%pi). So I think solution (1) is better, even if it seems inelegant to do two independent checks.  You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=903190&group_id=4933 