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Re: [Help-gsl] How does this cycle https://github.com/ampl/gsl/blob/mast
Re: [Help-gsl] How does this cycle https://github.com/ampl/gsl/blob/master/linalg/svd.c#L117 work?
Mon, 19 Jun 2017 14:53:04 +0200
thank you for the paper. I do actually proceed by comparing this paper and
the algorithms in "Matrix Computations fourth Edition", Golub and Loan with
the code in https://github.com/ampl/gsl/blob/master/linalg/svd.c
<https://github.com/ampl/gsl/blob/master/linalg/svd.c#L117> *which should
This is why the the gls code has to be fully understood, especially in its,
apparenty, odd implementation, like this strange cycle
2017-06-19 11:35 GMT+02:00 Patrick Alken <address@hidden>:
> I don't know the answer to your question, but its probably more helpful
> to take a look at the SVD algorithm description in Golub and Van Loan,
> on which the GSL code is probably based. Also its probably worthwhile to
> look at the original paper, which I found here:
> There is a complete pseudo-code writeup given in section 4.
> On 06/16/2017 04:19 PM, Marco Ippolito wrote:
> > Hi all
> > I do not undderstand this while cycle :
> > https://github.com/ampl/gsl/blob/master/linalg/svd.c#L117
> > It seems to me that the only time when b is decremented is here:
> > https://github.com/ampl/gsl/blob/master/linalg/svd.c#L123
> > so when fbm1 == 0.0 where fb1 is the value of f at index = b-1 :
> > https://github.com/ampl/gsl/blob/master/linalg/svd.c#L119
> > Since I'm trying to write my own C++11 code based on GSL code, I would
> > to understand how it can work.
> > Any ideas?
> > Looking forward to your kind help.
> > Marco