Re: [ublas] LAPACK using GEEV

Subject: Re: [ublas] LAPACK using GEEV
From: Kraus Philipp (philipp.kraus_at_[hidden])
Date: 2010-07-05 15:37:45

Am 05.07.2010 um 21:27 schrieb Marco Guazzone:

> On Mon, Jul 5, 2010 at 8:35 PM, Kraus Philipp
> <philipp.kraus_at_[hidden]> wrote:
>> Hi,
>> thanks for the answers to my last posting, but I had a mistake. I  
>> don't need
>> the eigenvalues of a symmetric real matrix, otherwise I need the  
>> values of a
>> squared real matrix.
>> I have found the DGEEV in the LAPACk and try to translate it to the  
>> Boost
>> bindings with:
>> T is set to double.
>> ublas::matrix<T, ublas::column_major> l_matrix( size, size);
>> // filling
>> ublas::vector<T> l_eigval(l_matrix.size1());
>>
>>
>>
>> ublas::vector<T> x(l_matrix.size1());
>> ublas::matrix<T, ublas::column_major>  
>> y(l_matrix.size1(),l_matrix.size1());
>> ublas::matrix<T, ublas::column_major>  
>> z(l_matrix.size1(),l_matrix.size1());
>>
>>
>>
>> lapack::geev( 'U', 'L', l_matrix, l_eigval,  x,y,z,
>> lapack::optimal_workspace() );
>>
>
> The values of the first and second arguments are wrong.
> Only 'V' or 'N' are admissible values:
>
> See: http://www.netlib.org/lapack/double/dgeev.f

Ohhhh, thanks, I had read always the link, but I had forgotten them

Now works perfect