Optimization doing more function evaluations than claimed
- To: mathgroup at smc.vnet.net
- Subject: [mg67333] Optimization doing more function evaluations than claimed
- From: "Solomon, Joshua" <J.A.Solomon at city.ac.uk>
- Date: Sun, 18 Jun 2006 05:13:38 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
After months of waiting, I finally got a good reply from WRI. Details below: On 15/6/06 17:30, "support at wolfram.com" <support at wolfram.com> wrote: > From: "Solomon, Joshua" Date: Fri, 13 Jan 2006 To: mathgroup at smc.vnet.net > > Dear W.R.T.S. > > Gareth Russell raised this issue on the newsgroup back in May and I echoed it > last month ( > http://groups.google.co.uk/group/comp.soft-sys.math.mathematica/browse_threa > d/thread/1d6ac336227232aa/cc7e5b6aa1d4a829?lnk=st&q=group%3A*mathematica*+au > thor%3Asolomon&rnum=1&hl=en#cc7e5b6aa1d4a829 ). No one seems to have replied. > I was wondering if this were a known bug, or even possibly a feature! For > reference: In[1]:= {$Version, $ReleaseNumber} Out[1]= {5.1 for Mac > OS X (October 25, 2004),0} > ----------------------------------------------------------------------- > > Mr. Solomon, > > Look at the output from EvaluationMonitor with InputForm. This is probably > coming from finite difference evaluation of derivatives. > > When I added InputForm wrappers to the Print to see all 16 digits, the small > variations in the parameters are visible. Here is an excerpt. > > In[5]:= FindMinimum[err = dummy[a, b, p, pMinusQ], {{a, 10}, {b, 0.03}, {p, > 3}, {pMinusQ, 0.44}}, EvaluationMonitor :> Print[ "err=", InputForm[err], " > a=", InputForm[a], " b=", InputForm[b], " p=", InputForm[p], " pMinusQ=", > InputForm[pMinusQ]]] > > ... > > Bruce Miller Technical Support Wolfram Research, Inc. support at wolfram.com > > ----------------------------------------------------------------------------