From: SourceForge.net <noreply@so...>  20031130 22:59:25

Bugs item #851765, was opened at 20031130 17:59 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=851765&group_id=4933 Category: None Group: None Status: Open Resolution: None Priority: 5 Submitted By: Stavros Macrakis (macrakis) Assigned to: Nobody/Anonymous (nobody) Summary: sum mishandles assume scopes Initial Comment: assume(i>=a); [i >= a] facts(); [i >= a] so far, so good sum(i,i,a,b)$ facts() [] oops! It removed the assumption is(i>=a) MACSYMA was unable to evaluate the predicate: i >= a The problem is that dosum adds the assumption a<=i<=b, and then removes it when it's done. But it does this in the global database, not a local one. So it also removes any preexisting identical assumption. It also ignores any inconsistent assumptions: assume(a>i) sum(i,i,a,b) => no error message This is sort of defensible on the grounds that the inner 'i' really isn't the same variable as the global 'i' (as though Maxima understood that)... except that it *is* obeying the global assumptions: assume(i<0) sum(abs(i),i,1,a) => 'sum(i,i,1,a)  You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=851765&group_id=4933 