Re: deterministic integration
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- Subject: [mg129981] Re: deterministic integration
- From: Alex Krasnov <akrasnov at eecs.berkeley.edu>
- Date: Sat, 2 Mar 2013 03:43:51 -0500 (EST)
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On Wed, 27 Feb 2013, daniel.lichtblau0 at gmail.com wrote: > Integrate uses a very large number of time-constrained computations, and some of them also use time constraints under the hood. > > There is some amount of discussion of this here: > > http://library.wolfram.com/infocenter/Conferences/5832/ > > A revised/updated version may be found here: > > http://www.sigsam.org/cca/issues/issue175.html > > See in particular section 5.7. Thank you for the detailed information. One clarification: are time constraints and associated non-determinism limited to definite integration in the current implementation or is there an example from indefinite integration? > As for effectively setting all time constraints to infinity, this might by and large work (except there are also several places where Integrate code bypasses the evaluator for time-constraining). > > Unprotect[TimeConstrained]; > TimeConstrained[expr_,args___] := expr > > This alters toe speed of your example above from 10 seconds to a minute; plan accordingly. Interesting. On my system (Mathematica 8.0.4), this does not make a significant timing difference but does appear to achieve the desired result. Alex