## Search found 3 matches

- Wed Jul 07, 2010 12:35 pm
- Forum: User discussion
- Topic: Problem with magmablas_dgemvt
- Replies:
**1** - Views:
**7409**

### Problem with magmablas_dgemvt

I gather that magmablas_dgemvt is supposed to compute y = A^t x, where A is n x m, x is n x 1, and y is m x 1. However, the function appears to compute only the first n elements of y. Thus, results are correct if m <= n, but incorrect otherwise. Below is a program, and its output, to illustrate the ...

- Tue Jul 06, 2010 9:52 am
- Forum: User discussion
- Topic: magma dgeqrs_gpu/dgeqrf_gpu2 interoperability
- Replies:
**2** - Views:
**8538**

### Re: magma dgeqrs_gpu/dgeqrf_gpu2 interoperability

Just to follow up on my original question... My usage of magma_dgeqrs is returning incorrect results. Below is a program, and its output, to illustrate the problem. In it, a symmetric positive-definite matrix A is defined and inverted using QR factorization. Specifically, magma_dgeqrf_gpu2 is used t...

- Thu Jul 01, 2010 5:43 pm
- Forum: User discussion
- Topic: magma dgeqrs_gpu/dgeqrf_gpu2 interoperability
- Replies:
**2** - Views:
**8538**

### magma dgeqrs_gpu/dgeqrf_gpu2 interoperability

The definition for 'magma_dgeqrs_gpu' is int magma_dgeqrs_gpu(int *m, int *n, int *nrhs, double *a, int *lda, double *tau, double *c, int *ldc, double *work, int *lwork, double *td, int *info); and its documentation (p.41) states that the 'td' argument "is the output (the 9th argument) of magma_dgeq...