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Topic: Lapack spptrf function
Replies: 10   Last Post: Apr 12, 2013 11:08 AM

 Messages: [ Previous | Next ]
 Francesco Perrone Posts: 39 Registered: 5/2/12
Re: Lapack spptrf function
Posted: Apr 11, 2013 3:07 AM

Dear Mr. Tursa,

I have a certain n*n matrix. Then calling

my_matrix = nn_matrix(itril(size(nn_matrix)));

I am able to wrap it into a lower triangular factor.

Afterwards, I manipulate my_matrix by means of a coherence function; the outcome, for only one step of the above mentioned FOR loop, is

Coh_u = exp(-a.*my_matrix.*sqrt((f(ii)/Uhub).^2 + (0.12/Lc).^2)).*(df.*psd(ii,1));

Therefore, Coh_u is alread packed as spptrf input.

Then I call the lapack wrapper as follows:

[C1u,C2u,HH_u,C3u] = lapack('spptrf','L',size(nn_matrix,1),Coh_u,0);

HH_u is the expected result.

I would more than appreciate if you could write a mex file of the spptrf function for me. Unfortunately I started only now learning some C++ and it would require a long time for me to catch up with mex file.

Look really forward to hearing from you.

Date Subject Author
4/9/13 Francesco Perrone
4/10/13 Steven Lord
4/10/13 Francesco Perrone
4/10/13 Steven Lord
4/10/13 James Tursa
4/10/13 James Tursa
4/11/13 Francesco Perrone
4/11/13 James Tursa
4/11/13 Francesco Perrone
4/12/13 Francesco Perrone
4/12/13 James Tursa