Opened 7 years ago

Last modified 4 years ago

#15747 new defect

bus or segmentation fault in integral computation

Reported by: tmonteil Owned by:
Priority: critical Milestone: sage-6.5
Component: symbolics Keywords: integral, symbolic
Cc: Merged in:
Authors: Reviewers:
Report Upstream: N/A Work issues:
Branch: Commit:
Dependencies: Stopgaps:


From this ask question:

sage: ys=0.06+2*(x-0.0275)
sage: xs=ys/1.516
sage: i=1/(xs/(1+xs)-x/(1+x))
sage: integral(i,x)
250/121*x^2 + 423541/58564*x + 86958139/28344976*log(484*x + 5)

But, the same integral with boundaries:

sage: integral(i,x,0,0.275)

leads to a series of lines of the form:

;;; Detected access to protected memory, also kwown as 'bus or segmentation fault'.
;;; Jumping to the outermost toplevel prompt

Change History (6)

comment:1 Changed 7 years ago by kcrisman

I can confirm that this problem also occurs with the integral to 11/40.

That said,

sage: i
1/((1.31926121372032*x + 0.00329815303430079)/(1.31926121372032*x + 1.00329815303430) - x/(x + 1))

and usually Maxima does not particularly like integrating floating point things exactly, because it sort of doesn't make sense.

sage: numerical_integral(i,0,0.275)
(12.325862793647284, 4.191806193893343e-11)

comment:2 Changed 7 years ago by vbraun_spam

  • Milestone changed from sage-6.1 to sage-6.2

comment:3 Changed 7 years ago by vbraun_spam

  • Milestone changed from sage-6.2 to sage-6.3

comment:4 Changed 6 years ago by vbraun_spam

  • Milestone changed from sage-6.3 to sage-6.4

comment:5 Changed 6 years ago by rws

  • Milestone changed from sage-6.4 to sage-6.5
  • Priority changed from major to critical

comment:6 Changed 4 years ago by jakobkroeker

Still an issue

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