Re: [Lapackpp-devel] SVD that ignores U, Sigma or VT

[Christian S. <sti...@tu...>]

Am Freitag, 3. September 2004 21:34 schrieb Jacob \(Jack\) Gryn:
> It might get a little confusing to implement, or to understand, but as long
> as things don't change for those who want the FULL SVD, it should be ok.
>
> The only other probs I can think of is that the LWORK variable may be
> different if JOBZ is different; also, if a number is too big (hence the
> reason to ignore part of the SVD, LWORK may also get much larger.
>
> Would you mind implementing it?

Ok, I just committed this into lasvd.h and lasvd.cc. Do you think you could 
test all cases of interest? I only made sure that the code makes sense, but I 
didn't actually test any of the routines -- they might well be broken.

Also, I committed the matrix multiplication when you only want the diagonal, 
in blas3pp.h (formerly blas3++.h). Again, you need to check whether it 
calculates the right thing -- it might as well crash on each call. But maybe 
it works :-)

Christian