[Insight-users] speed of svd

John Biddiscombe john . biddiscombe at mirada-solutions . com
Thu, 20 Nov 2003 11:05:57 -0000


I think you'll find that vxl/vnl code uses linpack rather than Lapack
(for svd at least) whereas Matlab probably uses lapack.

JB

> -----Original Message-----
> From: insight-users-admin at itk . org=20
> [mailto:insight-users-admin at itk . org] On Behalf Of Bing Jian
> Sent: 20 November 2003 03:49
> To: Insight-Users at itk . org
> Subject: [Insight-users] speed of svd
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> Hi, everyone,
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>     I assumed that C/C++ code would be faster than Matlab.
> But to my surprise, I found that svd routine in matlab is=20
> much faster than the one in vxl. I tried it on a 660*660=20
> matrix, it took matlab <5 seconds. While in using vnl_svd, it=20
> took about more than 20 seconds.
>    Does someone has an idea about this?
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>    Thanks in advance!
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> --=20
> Best wishes,
> Bing Jian
> bjian at cise . ufl . edu
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