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Re: trired/triql and EOF/PCA [message #28975]

Sat, 26 January 2002 09:58

the_cacc
Messages: 104
Registered: October 2001

Senior Member

wmc@bas.ac.uk wrote in message news:<3c512bf9@news.nwl.ac.uk>...
> ..finding eigenvectors of a symmetric matrix.

I'm no expert on eigenvalue decomposition but I think singular value
decomposition may be related (IDL routine "SVDC"). Pre-IDL 5.4, this
had the no. of iterations hard-coded to be 20 so it fell down for
moderate matrix sizes. Now there is an ITMAX keyword, which lets you
set the max. no. of iterations. If you hassle IDL customer support you
*may* be able to persuade them to provide such a keyword in the
TRIRED/TRIQL functions. But that's for the future... As for doing
partial decompositions, I don't think IDL has one.

Ciao.

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[Message index]

		Re: trired/triql and EOF/PCA By: the_cacc on Sat, 26 January 2002 09:58
		Re: trired/triql and EOF/PCA By: k-bowman on Fri, 25 January 2002 10:06
		Re: trired/triql and EOF/PCA By: the_cacc on Sun, 27 January 2002 15:18

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