#8321: numerical integration with arbitrary precision
-------------------------+--------------------------------------------------
   Reporter:  burcin     |          Owner:  burcin              
       Type:  defect     |         Status:  needs_work          
   Priority:  major      |      Milestone:  sage-4.7.2          
  Component:  symbolics  |       Keywords:  numerics,integration
Work_issues:             |       Upstream:  N/A                 
   Reviewer:             |         Author:  Stefan Reiterer     
     Merged:             |   Dependencies:                      
-------------------------+--------------------------------------------------

Comment(by zimmerma):

 Replying to [comment:28 kcrisman]:
 > This should really be finished and fixed.  Does anyone have any
 objection to something that does what Stefan implements (using mpmath) but
 then has lots of examples in numerical integration and `integrate` warning
 people not to trust floating-point, even with high precision,
 calculations?  Otherwise this ticket could get doomed by the "must be
 perfect" problem.

 we are still waiting for comparison figures for errors and timings (see
 comment [comment:12]).
 In those comparisons, I'd like to have arbitrary precision examples (say
 20, 50, 100, 200, 500
 and 1000 digits).

 > Are there specific places where this patch is causing incorrect or worse
 behavior?  Burcin's example seems to be equally bad for both, and I
 disagree with maldun that we shouldn't return symbolic answers.  At some
 point you have to make a decision, and the definite integral should
 naturally be symbolic if at all possible.

 of course {{{integrate(...)}}} will first give a symbolic result if any,
 then {{{integrate(...).n()}}} will evaluate numerically this symbolic
 value.
 We should explain in the documentation of {{{integrate}}} how to avoid the
 symbolic evaluation
 (for example adding the {{{hold}}} option). Anyway this is a different
 issue than this ticket.

 Paul

-- 
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/8321#comment:29>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica, 
and MATLAB

-- 
You received this message because you are subscribed to the Google Groups 
"sage-trac" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to 
[email protected].
For more options, visit this group at 
http://groups.google.com/group/sage-trac?hl=en.

Reply via email to