LAPACK 3.12.0
LAPACK: Linear Algebra PACKage
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◆ zlascl()

subroutine zlascl ( character type,
integer kl,
integer ku,
double precision cfrom,
double precision cto,
integer m,
integer n,
complex*16, dimension( lda, * ) a,
integer lda,
integer info )

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

Download ZLASCL + dependencies [TGZ] [ZIP] [TXT]

Purpose:
!>
!> ZLASCL multiplies the M by N complex 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
[in]TYPE
!>          TYPE is CHARACTER*1
!>          TYPE 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 ZGBTRF for storage details.
!>
[in]KL
!>          KL is INTEGER
!>          The lower bandwidth of A.  Referenced only if TYPE = 'B',
!>          'Q' or 'Z'.
!>
[in]KU
!>          KU is INTEGER
!>          The upper bandwidth of A.  Referenced only if TYPE = 'B',
!>          'Q' or 'Z'.
!>
[in]CFROM
!>          CFROM is DOUBLE PRECISION
!>
[in]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.
!>
[in]M
!>          M is INTEGER
!>          The number of rows of the matrix A.  M >= 0.
!>
[in]N
!>          N is INTEGER
!>          The number of columns of the matrix A.  N >= 0.
!>
[in,out]A
!>          A is COMPLEX*16 array, dimension (LDA,N)
!>          The matrix to be multiplied by CTO/CFROM.  See TYPE for the
!>          storage type.
!>
[in]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.
!>
[out]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.