slag2d (l) - Linux Man Pages
slag2d: converts a SINGLE PRECISION matrix, SA, to a DOUBLE PRECISION matrix, A
Command to display
slag2d manual in Linux:
$ man l slag2d
SLAG2D - converts a SINGLE PRECISION matrix, SA, to a DOUBLE PRECISION matrix, A
- SUBROUTINE SLAG2D(
M, N, SA, LDSA, A, LDA, INFO )
INFO, LDA, LDSA, M, N
SA( LDSA, * )
PRECISION A( LDA, * )
SLAG2D converts a SINGLE PRECISION matrix, SA, to a DOUBLE
PRECISION matrix, A.
Note that while it is possible to overflow while converting
from double to single, it is not possible to overflow when
converting from single to double.
This is an auxiliary routine so there is no argument checking.
- M (input) INTEGER
The number of lines of the matrix A. M >= 0.
- N (input) INTEGER
The number of columns of the matrix A. N >= 0.
- SA (input) REAL array, dimension (LDSA,N)
On entry, the M-by-N coefficient matrix SA.
- LDSA (input) INTEGER
The leading dimension of the array SA. LDSA >= max(1,M).
- A (output) DOUBLE PRECISION array, dimension (LDA,N)
On exit, the M-by-N coefficient matrix A.
- LDA (input) INTEGER
The leading dimension of the array A. LDA >= max(1,M).
- INFO (output) INTEGER
= 0: successful exit
End of SLAG2D
Pages related to slag2d
- slag2d (3)
- slag2 (l) - computes the eigenvalues of a 2 x 2 generalized eigenvalue problem A - w B, with scaling as necessary to avoid over-/underflow
- slags2 (l) - computes 2-by-2 orthogonal matrices U, V and Q, such that if ( UPPER ) then Uaq*A*Q = Uaq*( A1 A2 )*Q = ( x 0 ) ( 0 A3 ) ( x x ) and Vaq*B*Q = Vaq*( B1 B2 )*Q = ( x 0 ) ( 0 B3 ) ( x x ) or if ( .NOT.UPPER ) then Uaq*A*Q = Uaq*( A1 0 )*Q = ( x x ) ( A2 A3 ) ( 0 x ) and Vaq*B*Q = Vaq*( B1 0 )*Q = ( x x ) ( B2 B3 ) ( 0 x ) The rows of the transformed A and B are parallel, where U = ( CSU SNU ), V = ( CSV SNV ), Q = ( CSQ SNQ ) ( -SNU CSU ) ( -SNV CSV ) ( -SNQ CSQ ) Zaq denotes the transpose of Z
- slagtf (l) - factorizes the matrix (T - lambda*I), where T is an n by n tridiagonal matrix and lambda is a scalar, as T - lambda*I = PLU,
- slagtm (l) - performs a matrix-vector product of the form B := alpha * A * X + beta * B where A is a tridiagonal matrix of order N, B and X are N by NRHS matrices, and alpha and beta are real scalars, each of which may be 0., 1., or -1
- slagts (l) - may be used to solve one of the systems of equations (T - lambda*I)*x = y or (T - lambda*I)aq*x = y,
- slagv2 (l) - computes the Generalized Schur factorization of a real 2-by-2 matrix pencil (A,B) where B is upper triangular
- sla_gbamv (l) - performs one of the matrix-vector operations y := alpha*abs(A)*abs(x) + beta*abs(y),