zung2l
zung2l - generate an m by n complex matrix Q with orthonormal columns,
SUBROUTINE ZUNG2L( M, N, K, A, LDA, TAU, WORK, INFO)
DOUBLE COMPLEX A(LDA,*), TAU(*), WORK(*)
INTEGER M, N, K, LDA, INFO
SUBROUTINE ZUNG2L_64( M, N, K, A, LDA, TAU, WORK, INFO)
DOUBLE COMPLEX A(LDA,*), TAU(*), WORK(*)
INTEGER*8 M, N, K, LDA, INFO
SUBROUTINE UNG2L( M, [N], [K], A, [LDA], TAU, [WORK], [INFO])
COMPLEX(8), DIMENSION(:) :: TAU, WORK
COMPLEX(8), DIMENSION(:,:) :: A
INTEGER :: M, N, K, LDA, INFO
SUBROUTINE UNG2L_64( M, [N], [K], A, [LDA], TAU, [WORK], [INFO])
COMPLEX(8), DIMENSION(:) :: TAU, WORK
COMPLEX(8), DIMENSION(:,:) :: A
INTEGER(8) :: M, N, K, LDA, INFO
#include <sunperf.h>
void zung2l(int m, int n, int k, doublecomplex *a, int lda, doublecomplex *tau, int *info);
void zung2l_64(long m, long n, long k, doublecomplex *a, long lda, doublecomplex *tau, long *info);
zung2l L generates an m by n complex matrix Q with orthonormal columns,
which is defined as the last n columns of a product of k elementary
reflectors of order m
Q = H(k) . . . H(2) H(1)
as returned by CGEQLF.
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* M (input)
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The number of rows of the matrix Q. M >= 0.
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* N (input)
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The number of columns of the matrix Q. M >= N >= 0.
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* K (input)
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The number of elementary reflectors whose product defines the
matrix Q. N >= K >= 0.
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* A (input/output)
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On entry, the (n-k+i)-th column must contain the vector which
defines the elementary reflector H(i), for i = 1,2,...,k, as
returned by CGEQLF in the last k columns of its array
argument A.
On exit, the m-by-n matrix Q.
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* LDA (input)
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The first dimension of the array A. LDA >= max(1,M).
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* TAU (input)
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TAU(i) must contain the scalar factor of the elementary
reflector H(i), as returned by CGEQLF.
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* WORK (workspace)
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dimension(N)
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* INFO (output)
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