## Search found 6 matches

Sat Oct 24, 2015 5:49 pm
Forum: User discussion
Topic: Equivalent routines for eigs function in Matlab
Replies: 2
Views: 2013

### Re: Equivalent routines for eigs function in Matlab

Hi, Thanks for the reply. I tried to find the K largest eigen vectors using dsyevdx routine. However, it seems to be much slower than the matlab eigs function. I have a 11000 * 11000 symmetric matrix (Also all the eigen values were between 0 to 1) and extracted the first 10 eigen vectors of the matr...
Fri Oct 23, 2015 8:25 pm
Forum: User discussion
Topic: LOBPCG method for Eigen Value Computation.
Replies: 4
Views: 2230

### Re: LOBPCG method for Eigen Value Computation.

Thanks for the info, Stan
Fri Oct 23, 2015 8:23 pm
Forum: User discussion
Topic: Equivalent routines for eigs function in Matlab
Replies: 2
Views: 2013

### Equivalent routines for eigs function in Matlab

Hi, Are there any routines which compute the K largest Eigenvectors of a dense and a symmetric matrix (It is Positive semi definite as well) in Magma? If there is one, what algorithm does it use? I know that matlab uses Arnoldi/Lanczos iterations to compute the required Eigenvectors. With regards, N...
Sun Oct 18, 2015 6:59 pm
Forum: User discussion
Topic: LOBPCG method for Eigen Value Computation.
Replies: 4
Views: 2230

### Re: LOBPCG method for Eigen Value Computation.

Hi Hartwig, Thanks for the reply. I tried the use the solver using the method suggested by you and it helped me to find the eigenvalues correctly. However instead of providing the k-largest eigen values, it provides me with K-smallest ones. Is there a setting for the algorithm which calculates the l...
Sun Oct 18, 2015 7:20 am
Forum: User discussion
Topic: LOBPCG method for Eigen Value Computation.
Replies: 4
Views: 2230

### LOBPCG method for Eigen Value Computation.

Hi, I am new to MAGMA. I want to find the top K(K is a very small number) eigen vectors of a sparse symmetric matrix whose dimension is more than 30000. In addition, the matrix in consideration is positive semi definite. However, I am not able to understand the arguments that needs to be passed to t...
Sun Oct 12, 2014 6:29 am
Forum: User discussion
Topic: Eigenvalue routine in Magma
Replies: 1
Views: 1980

### Eigenvalue routine in Magma

Hi, I have to calculate the eigenvalues 1000 symmetric matrices and the dimension of these matrices are very small( about 10 * 10) in each run. All these matrices are computed on the GPU. As far as i understand from the magma routines, the eigenvalue routine for GPUs transfers these matrices to the ...