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https://issues.apache.org/jira/browse/MATH-621?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13076194#comment-13076194
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Gilles commented on MATH-621:
-----------------------------
Dietmar,
I think I've come across a bug in function "rescue". At line 2443 (of the Java
translation I use for comparison, i.e. the one with "ScopedPtr"):
{code}
i__2 = ndim;
for (ip = npt; ip <= i__2; ip++) {
sum += bmat.get(ip + j * bmat_dim1) * w.get(ip);
}
{code}
Whereas, in the original Fortran code (at line 1544):
{noformat}
DO 220 IP=NPT+1,NDIM
220 SUM=SUM+BMAT(IP,J)*W(IP)
{noformat}
Can you confirm?
If indeed, the loop should start at "npt + 1", I've made the change; but tests
still all pass! Does this mean that the one exercising rescue is too lenient?
Trying to remove the "w" ("split" work space) from "rescue" provides many
possibilities for my own mistakes; thus I am a little scared that they would
also go unnoticed...
> BOBYQA is missing in optimization
> ---------------------------------
>
> Key: MATH-621
> URL: https://issues.apache.org/jira/browse/MATH-621
> Project: Commons Math
> Issue Type: New Feature
> Affects Versions: 3.0
> Reporter: Dr. Dietmar Wolz
> Fix For: 3.0
>
> Attachments: BOBYQA.math.patch, BOBYQA.v02.math.patch, bobyqa.zip,
> bobyqaoptimizer0.4.zip, bobyqav0.3.zip
>
> Original Estimate: 8h
> Remaining Estimate: 8h
>
> During experiments with space flight trajectory optimizations I recently
> observed, that the direct optimization algorithm BOBYQA
> http://plato.asu.edu/ftp/other_software/bobyqa.zip
> from Mike Powell is significantly better than the simple Powell algorithm
> already in commons.math. It uses significantly lower function calls and is
> more reliable for high dimensional problems. You can replace CMA-ES in many
> more application cases by BOBYQA than by the simple Powell optimizer.
> I would like to contribute a Java port of the algorithm.
> I maintained the structure of the original FORTRAN code, so the
> code is fast but not very nice.
> License status: Michael Powell has sent the agreement via snail mail
> - it hasn't arrived yet.
> Progress: The attached patch relative to the trunk contains both the
> optimizer and the related unit tests - which are all green now.
> Performance:
> Performance difference (number of function evaluations)
> PowellOptimizer / BOBYQA for different test functions (taken from
> the unit test of BOBYQA, dimension=13 for most of the
> tests.
> Rosen = 9350 / 1283
> MinusElli = 118 / 59
> Elli = 223 / 58
> ElliRotated = 8626 / 1379
> Cigar = 353 / 60
> TwoAxes = 223 / 66
> CigTab = 362 / 60
> Sphere = 223 / 58
> Tablet = 223 / 58
> DiffPow = 421 / 928
> SsDiffPow = 614 / 219
> Ackley = 757 / 97
> Rastrigin = 340 / 64
> The number for DiffPow should be dicussed with Michael Powell,
> I will send him the details.
> Open Problems:
> Some checkstyle violations because of the original Fortran source:
> - Original method comments were copied - doesn't follow javadoc standard
> - Multiple variable declarations in one line as in the original source
> - Problems related to "goto" conversions:
> "gotos" not convertible in loops were transated into a finite automata
> (switch statement)
> "no default in switch"
> "fall through from previos case in switch"
> which usually are bad style make no sense here.
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