From: SourceForge.net <noreply@so...>  20041027 14:14:19

Bugs item #626607, was opened at 20021022 02:30 Message generated for change (Comment added) made by vidybida You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=626607&group_id=4933 Category: None Group: None Status: Open Resolution: None Priority: 5 Submitted By: Stavros Macrakis (macrakis) Assigned to: Nobody/Anonymous (nobody) Summary: Defint doesn't clean up asksign db Initial Comment: >> integrate(x^n,x,1,inf); << Is n positive, negative, or zero? >> pos; << Integral is divergent So far, so good. Now: >> asksign(n); << pos; That is, the asksign database still contains the fact that n>0. This should have been removed when defint exited. This problem doesn't happen when the integral is convergent.  Comment By: Alexander VIDYBIDA (vidybida) Date: 20041027 17:14 Message: Logged In: YES user_id=927510 The obsolete info, which have to be removed after estimated a divergent integral, can be kicked out by "IS" oporator: (%i1) integrate(EXP(la*t)*la,t,0,INF); Is la positive, negative, or zero? n; Integral is divergent  an error. Quitting. To debug this try DEBUGMODE(TRUE); (%i2) integrate(EXP(la*t)*la,t,0,INF); Integral is divergent  an error. Quitting. To debug this try DEBUGMODE(TRUE); HOW DOES IT KNOW ? (%i3) is(la<0); MACSYMA was unable to evaluate the predicate: la < 0  an error. Quitting. To debug this try DEBUGMODE(TRUE); (%i4) integrate(EXP(la*t)*la,t,0,INF); Integral is divergent  an error. Quitting. To debug this try DEBUGMODE(TRUE); HOW DOES IT KNOW ? (%i5) is(la>0); MACSYMA was unable to evaluate the predicate: la > 0  an error. Quitting. To debug this try DEBUGMODE(TRUE); (%i6) integrate(EXP(la*t)*la,t,0,INF); Integral is divergent  an error. Quitting. To debug this try DEBUGMODE(TRUE); HOW DOES IT KNOW ? (%i7) is(la=0); (%o7) FALSE NOW THE INFO IS KICKED OUT (%i8) integrate(EXP(la*t)*la,t,0,INF); Is la positive, negative, or zero? p; (%o8) 1  You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=626607&group_id=4933 