dlascl (l) - Linux Manuals

dlascl: multiplies the M by N real matrix A by the real scalar CTO/CFROM

NAME

DLASCL - multiplies the M by N real matrix A by the real scalar CTO/CFROM

SYNOPSIS

SUBROUTINE DLASCL(
TYPE, KL, KU, CFROM, CTO, M, N, A, LDA, INFO )

    
CHARACTER TYPE

    
INTEGER INFO, KL, KU, LDA, M, N

    
DOUBLE PRECISION CFROM, CTO

    
DOUBLE PRECISION A( LDA, * )

PURPOSE

DLASCL multiplies the M by N real matrix A by the real scalar CTO/CFROM. This is done without over/underflow as long as the final result CTO*A(I,J)/CFROM does not over/underflow. TYPE specifies that A may be full, upper triangular, lower triangular, upper Hessenberg, or banded.

ARGUMENTS

TYPE (input) CHARACTER*1
TYPE indices the storage type of the input matrix. = aqGaq: A is a full matrix.
= aqLaq: A is a lower triangular matrix.
= aqUaq: A is an upper triangular matrix.
= aqHaq: A is an upper Hessenberg matrix.
= aqBaq: A is a symmetric band matrix with lower bandwidth KL and upper bandwidth KU and with the only the lower half stored. = aqQaq: A is a symmetric band matrix with lower bandwidth KL and upper bandwidth KU and with the only the upper half stored. = aqZaq: A is a band matrix with lower bandwidth KL and upper bandwidth KU.
KL (input) INTEGER
The lower bandwidth of A. Referenced only if TYPE = aqBaq, aqQaq or aqZaq.
KU (input) INTEGER
The upper bandwidth of A. Referenced only if TYPE = aqBaq, aqQaq or aqZaq.
CFROM (input) DOUBLE PRECISION
CTO (input) DOUBLE PRECISION The matrix A is multiplied by CTO/CFROM. A(I,J) is computed without over/underflow if the final result CTO*A(I,J)/CFROM can be represented without over/underflow. CFROM must be nonzero.
M (input) INTEGER
The number of rows of the matrix A. M >= 0.
N (input) INTEGER
The number of columns of the matrix A. N >= 0.
A (input/output) DOUBLE PRECISION array, dimension (LDA,N)
The matrix to be multiplied by CTO/CFROM. See TYPE for the storage type.
LDA (input) INTEGER
The leading dimension of the array A. LDA >= max(1,M).
INFO (output) INTEGER
0 - successful exit <0 - if INFO = -i, the i-th argument had an illegal value.

Pages related to dlascl

  • dlascl (3)
  • dlascl2 (l) - performs a diagonal scaling on a vector
  • dlas2 (l) - computes the singular values of the 2-by-2 matrix [ F G ] [ 0 H ]
  • dlasd0 (l) - a divide and conquer approach, DLASD0 computes the singular value decomposition (SVD) of a real upper bidiagonal N-by-M matrix B with diagonal D and offdiagonal E, where M = N + SQRE
  • dlasd1 (l) - computes the SVD of an upper bidiagonal N-by-M matrix B,
  • dlasd2 (l) - merges the two sets of singular values together into a single sorted set
  • dlasd3 (l) - finds all the square roots of the roots of the secular equation, as defined by the values in D and Z
  • dlasd4 (l) - subroutine compute the square root of the I-th updated eigenvalue of a positive symmetric rank-one modification to a positive diagonal matrix whose entries are given as the squares of the corresponding entries in the array d, and that 0 <= D(i) < D(j) for i < j and that RHO > 0
  • dlasd5 (l) - subroutine compute the square root of the I-th eigenvalue of a positive symmetric rank-one modification of a 2-by-2 diagonal matrix diag( D ) * diag( D ) + RHO The diagonal entries in the array D are assumed to satisfy 0 <= D(i) < D(j) for i < j
  • dlasd6 (l) - computes the SVD of an updated upper bidiagonal matrix B obtained by merging two smaller ones by appending a row