COMPLEX routines for (complex) unitary, packed storageBDbidiagonal matrix
cupgtr
USAGE:
q, info = NumRu::Lapack.cupgtr( uplo, ap, tau, [:usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE CUPGTR( UPLO, N, AP, TAU, Q, LDQ, WORK, INFO )
* Purpose
* =======
*
* CUPGTR generates a complex unitary matrix Q which is defined as the
* product of n-1 elementary reflectors H(i) of order n, as returned by
* CHPTRD using packed storage:
*
* if UPLO = 'U', Q = H(n-1) . . . H(2) H(1),
*
* if UPLO = 'L', Q = H(1) H(2) . . . H(n-1).
*
* Arguments
* =========
*
* UPLO (input) CHARACTER*1
* = 'U': Upper triangular packed storage used in previous
* call to CHPTRD;
* = 'L': Lower triangular packed storage used in previous
* call to CHPTRD.
*
* N (input) INTEGER
* The order of the matrix Q. N >= 0.
*
* AP (input) COMPLEX array, dimension (N*(N+1)/2)
* The vectors which define the elementary reflectors, as
* returned by CHPTRD.
*
* TAU (input) COMPLEX array, dimension (N-1)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by CHPTRD.
*
* Q (output) COMPLEX array, dimension (LDQ,N)
* The N-by-N unitary matrix Q.
*
* LDQ (input) INTEGER
* The leading dimension of the array Q. LDQ >= max(1,N).
*
* WORK (workspace) COMPLEX array, dimension (N-1)
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument had an illegal value
*
* =====================================================================
*
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cupmtr
USAGE:
info, c = NumRu::Lapack.cupmtr( side, uplo, trans, m, ap, tau, c, [:usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE CUPMTR( SIDE, UPLO, TRANS, M, N, AP, TAU, C, LDC, WORK, INFO )
* Purpose
* =======
*
* CUPMTR overwrites the general complex M-by-N matrix C with
*
* SIDE = 'L' SIDE = 'R'
* TRANS = 'N': Q * C C * Q
* TRANS = 'C': Q**H * C C * Q**H
*
* where Q is a complex unitary matrix of order nq, with nq = m if
* SIDE = 'L' and nq = n if SIDE = 'R'. Q is defined as the product of
* nq-1 elementary reflectors, as returned by CHPTRD using packed
* storage:
*
* if UPLO = 'U', Q = H(nq-1) . . . H(2) H(1);
*
* if UPLO = 'L', Q = H(1) H(2) . . . H(nq-1).
*
* Arguments
* =========
*
* SIDE (input) CHARACTER*1
* = 'L': apply Q or Q**H from the Left;
* = 'R': apply Q or Q**H from the Right.
*
* UPLO (input) CHARACTER*1
* = 'U': Upper triangular packed storage used in previous
* call to CHPTRD;
* = 'L': Lower triangular packed storage used in previous
* call to CHPTRD.
*
* TRANS (input) CHARACTER*1
* = 'N': No transpose, apply Q;
* = 'C': Conjugate transpose, apply Q**H.
*
* M (input) INTEGER
* The number of rows of the matrix C. M >= 0.
*
* N (input) INTEGER
* The number of columns of the matrix C. N >= 0.
*
* AP (input) COMPLEX array, dimension
* (M*(M+1)/2) if SIDE = 'L'
* (N*(N+1)/2) if SIDE = 'R'
* The vectors which define the elementary reflectors, as
* returned by CHPTRD. AP is modified by the routine but
* restored on exit.
*
* TAU (input) COMPLEX array, dimension (M-1) if SIDE = 'L'
* or (N-1) if SIDE = 'R'
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by CHPTRD.
*
* C (input/output) COMPLEX array, dimension (LDC,N)
* On entry, the M-by-N matrix C.
* On exit, C is overwritten by Q*C or Q**H*C or C*Q**H or C*Q.
*
* LDC (input) INTEGER
* The leading dimension of the array C. LDC >= max(1,M).
*
* WORK (workspace) COMPLEX array, dimension
* (N) if SIDE = 'L'
* (M) if SIDE = 'R'
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument had an illegal value
*
* =====================================================================
*
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