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MAGMA
1.6.1
Matrix Algebra for GPU and Multicore Architectures
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Functions | |
magma_int_t | magma_ztsqrt_gpu (magma_int_t *m, magma_int_t *n, magmaDoubleComplex *A1, magmaDoubleComplex *A2, magma_int_t *lda, magmaDoubleComplex *tau, magmaDoubleComplex *work, magma_int_t *lwork, magmaDoubleComplex_ptr dwork, magma_int_t *info) |
ZGEQRF computes a QR factorization of a complex M-by-N matrix A: A = Q * R. More... | |
magma_int_t magma_ztsqrt_gpu | ( | magma_int_t * | m, |
magma_int_t * | n, | ||
magmaDoubleComplex * | A1, | ||
magmaDoubleComplex * | A2, | ||
magma_int_t * | lda, | ||
magmaDoubleComplex * | tau, | ||
magmaDoubleComplex * | work, | ||
magma_int_t * | lwork, | ||
magmaDoubleComplex_ptr | dwork, | ||
magma_int_t * | info | ||
) |
ZGEQRF computes a QR factorization of a complex M-by-N matrix A: A = Q * R.
[in] | m | INTEGER The number of rows of the matrix A. M >= 0. |
[in] | n | INTEGER The number of columns of the matrix A. N >= 0. |
[in,out] | A | COMPLEX_16 array on the GPU, dimension (LDA,N) On entry, the M-by-N matrix A. On exit, the elements on and above the diagonal of the array contain the min(M,N)-by-N upper trapezoidal matrix R (R is upper triangular if m >= n); the elements below the diagonal, with the array TAU, represent the orthogonal matrix Q as a product of min(m,n) elementary reflectors (see Further Details). |
[in] | lda | INTEGER The leading dimension of the array A. LDA >= max(1,M). |
[out] | tau | COMPLEX_16 array, dimension (min(M,N)) The scalar factors of the elementary reflectors (see Further Details). |
[out] | work | (workspace) COMPLEX_16 array, dimension (MAX(1,LWORK)) On exit, if INFO = 0, WORK[0] returns the optimal LWORK. Higher performance is achieved if WORK is in pinned memory, e.g. allocated using magma_malloc_pinned. |
[in] | lwork | INTEGER The dimension of the array WORK. LWORK >= (M+N+NB)*NB, where NB can be obtained through magma_get_zgeqrf_nb(M). If LWORK = -1, then a workspace query is assumed; the routine only calculates the optimal size of the WORK array, returns this value as the first entry of the WORK array, and no error message related to LWORK is issued. |
[out] | dwork | (workspace) COMPLEX_16 array on the GPU, dimension 2*N*NB, where NB can be obtained through magma_get_zgeqrf_nb(M). It starts with NB*NB blocks that store the triangular T matrices, followed by the NB*NB blocks of the diagonal inverses for the R matrix. |
[out] | info | INTEGER
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The matrix Q is represented as a product of elementary reflectors
Q = H(1) H(2) . . . H(k), where k = min(m,n).
Each H(i) has the form
H(i) = I - tau * v * v'
where tau is a complex scalar, and v is a complex vector with v(1:i-1) = 0 and v(i) = 1; v(i+1:m) is stored on exit in A(i+1:m,i), and tau in TAU(i).