SRC/dlascl.f(3)

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✨ NAME ✨

SRC/dlascl.f

✨ SYNOPSIS ✨

Functions/Subroutines

• subroutine dlascl (type, kl, ku, cfrom, cto, m, n, a, lda, info) — DLASCL multiplies a general rectangular matrix by a real scalar defined as cto/cfrom.

✨ Function/Subroutine Documentation ✨

subroutine dlascl (character type, integer kl, integer ku, double precision
    cfrom, double precision cto, integer m, integer n, double precision,
    dimension( lda, * ) a, integer lda, integer info)

DLASCL multiplies a general rectangular matrix by a real scalar defined as cto/cfrom.

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.

Parameters

• TYPE — TYPE is CHARACTER*1. It indices the storage type of the input matrix.
  • = 'G': A is a full matrix.
  • = 'L': A is a lower triangular matrix.
  • = 'U': A is an upper triangular matrix.
  • = 'H': A is an upper Hessenberg matrix.
  • = 'B': A is a symmetric band matrix with lower bandwidth KL and upper bandwidth KU and with the only the lower half stored.
  • = 'Q': A is a symmetric band matrix with lower bandwidth KL and upper bandwidth KU and with the only the upper half stored.
  • = 'Z': A is a band matrix with lower bandwidth KL and upper bandwidth KU. See DGBTRF for storage details.
• KL — KL is INTEGER. The lower bandwidth of A. Referenced only if TYPE = 'B', 'Q' or 'Z'.
• KU — KU is INTEGER. The upper bandwidth of A. Referenced only if TYPE = 'B', 'Q' or 'Z'.
• CFROM — CFROM is DOUBLE PRECISION.
• CTO — CTO is 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 — M is INTEGER. The number of rows of the matrix A. M >= 0.
• N — N is INTEGER. The number of columns of the matrix A. N >= 0.
• A — A is DOUBLE PRECISION array, dimension (LDA,N). The matrix to be multiplied by CTO/CFROM. See TYPE for the storage type.
• LDA — LDA is INTEGER. The leading dimension of the array A.
  • If TYPE = 'G', 'L', 'U', 'H', LDA >= max(1,M);
  • TYPE = 'B', LDA >= KL+1;
  • TYPE = 'Q', LDA >= KU+1;
  • TYPE = 'Z', LDA >= 2*KL+KU+1.
• INFO — INFO is INTEGER.
  • 0 - successful exit
  • <0 - if INFO = -i, the i-th argument had an illegal value.

Author

• Univ. of Tennessee
• Univ. of California Berkeley
• Univ. of Colorado Denver
• NAG Ltd.

Definition at line 142 of file dlascl.f.

✨ Author ✨

Generated automatically by Doxygen for LAPACK from the source code.

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