REAL routines for (real) orthogonal matrix
sorbdb
USAGE:
theta, phi, taup1, taup2, tauq1, tauq2, info, x11, x12, x21, x22 = NumRu::Lapack.sorbdb( trans, signs, m, x11, x12, x21, x22, [:lwork => lwork, :usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORBDB( TRANS, SIGNS, M, P, Q, X11, LDX11, X12, LDX12, X21, LDX21, X22, LDX22, THETA, PHI, TAUP1, TAUP2, TAUQ1, TAUQ2, WORK, LWORK, INFO )
* Purpose
* =======
*
* SORBDB simultaneously bidiagonalizes the blocks of an M-by-M
* partitioned orthogonal matrix X:
*
* [ B11 | B12 0 0 ]
* [ X11 | X12 ] [ P1 | ] [ 0 | 0 -I 0 ] [ Q1 | ]**T
* X = [-----------] = [---------] [----------------] [---------] .
* [ X21 | X22 ] [ | P2 ] [ B21 | B22 0 0 ] [ | Q2 ]
* [ 0 | 0 0 I ]
*
* X11 is P-by-Q. Q must be no larger than P, M-P, or M-Q. (If this is
* not the case, then X must be transposed and/or permuted. This can be
* done in constant time using the TRANS and SIGNS options. See SORCSD
* for details.)
*
* The orthogonal matrices P1, P2, Q1, and Q2 are P-by-P, (M-P)-by-
* (M-P), Q-by-Q, and (M-Q)-by-(M-Q), respectively. They are
* represented implicitly by Householder vectors.
*
* B11, B12, B21, and B22 are Q-by-Q bidiagonal matrices represented
* implicitly by angles THETA, PHI.
*
* Arguments
* =========
*
* TRANS (input) CHARACTER
* = 'T': X, U1, U2, V1T, and V2T are stored in row-major
* order;
* otherwise: X, U1, U2, V1T, and V2T are stored in column-
* major order.
*
* SIGNS (input) CHARACTER
* = 'O': The lower-left block is made nonpositive (the
* "other" convention);
* otherwise: The upper-right block is made nonpositive (the
* "default" convention).
*
* M (input) INTEGER
* The number of rows and columns in X.
*
* P (input) INTEGER
* The number of rows in X11 and X12. 0 <= P <= M.
*
* Q (input) INTEGER
* The number of columns in X11 and X21. 0 <= Q <=
* MIN(P,M-P,M-Q).
*
* X11 (input/output) REAL array, dimension (LDX11,Q)
* On entry, the top-left block of the orthogonal matrix to be
* reduced. On exit, the form depends on TRANS:
* If TRANS = 'N', then
* the columns of tril(X11) specify reflectors for P1,
* the rows of triu(X11,1) specify reflectors for Q1;
* else TRANS = 'T', and
* the rows of triu(X11) specify reflectors for P1,
* the columns of tril(X11,-1) specify reflectors for Q1.
*
* LDX11 (input) INTEGER
* The leading dimension of X11. If TRANS = 'N', then LDX11 >=
* P; else LDX11 >= Q.
*
* X12 (input/output) REAL array, dimension (LDX12,M-Q)
* On entry, the top-right block of the orthogonal matrix to
* be reduced. On exit, the form depends on TRANS:
* If TRANS = 'N', then
* the rows of triu(X12) specify the first P reflectors for
* Q2;
* else TRANS = 'T', and
* the columns of tril(X12) specify the first P reflectors
* for Q2.
*
* LDX12 (input) INTEGER
* The leading dimension of X12. If TRANS = 'N', then LDX12 >=
* P; else LDX11 >= M-Q.
*
* X21 (input/output) REAL array, dimension (LDX21,Q)
* On entry, the bottom-left block of the orthogonal matrix to
* be reduced. On exit, the form depends on TRANS:
* If TRANS = 'N', then
* the columns of tril(X21) specify reflectors for P2;
* else TRANS = 'T', and
* the rows of triu(X21) specify reflectors for P2.
*
* LDX21 (input) INTEGER
* The leading dimension of X21. If TRANS = 'N', then LDX21 >=
* M-P; else LDX21 >= Q.
*
* X22 (input/output) REAL array, dimension (LDX22,M-Q)
* On entry, the bottom-right block of the orthogonal matrix to
* be reduced. On exit, the form depends on TRANS:
* If TRANS = 'N', then
* the rows of triu(X22(Q+1:M-P,P+1:M-Q)) specify the last
* M-P-Q reflectors for Q2,
* else TRANS = 'T', and
* the columns of tril(X22(P+1:M-Q,Q+1:M-P)) specify the last
* M-P-Q reflectors for P2.
*
* LDX22 (input) INTEGER
* The leading dimension of X22. If TRANS = 'N', then LDX22 >=
* M-P; else LDX22 >= M-Q.
*
* THETA (output) REAL array, dimension (Q)
* The entries of the bidiagonal blocks B11, B12, B21, B22 can
* be computed from the angles THETA and PHI. See Further
* Details.
*
* PHI (output) REAL array, dimension (Q-1)
* The entries of the bidiagonal blocks B11, B12, B21, B22 can
* be computed from the angles THETA and PHI. See Further
* Details.
*
* TAUP1 (output) REAL array, dimension (P)
* The scalar factors of the elementary reflectors that define
* P1.
*
* TAUP2 (output) REAL array, dimension (M-P)
* The scalar factors of the elementary reflectors that define
* P2.
*
* TAUQ1 (output) REAL array, dimension (Q)
* The scalar factors of the elementary reflectors that define
* Q1.
*
* TAUQ2 (output) REAL array, dimension (M-Q)
* The scalar factors of the elementary reflectors that define
* Q2.
*
* WORK (workspace) REAL array, dimension (LWORK)
*
* LWORK (input) INTEGER
* The dimension of the array WORK. LWORK >= M-Q.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the WORK array, and no error
* message related to LWORK is issued by XERBLA.
*
* INFO (output) INTEGER
* = 0: successful exit.
* < 0: if INFO = -i, the i-th argument had an illegal value.
*
* Further Details
* ===============
*
* The bidiagonal blocks B11, B12, B21, and B22 are represented
* implicitly by angles THETA(1), ..., THETA(Q) and PHI(1), ...,
* PHI(Q-1). B11 and B21 are upper bidiagonal, while B21 and B22 are
* lower bidiagonal. Every entry in each bidiagonal band is a product
* of a sine or cosine of a THETA with a sine or cosine of a PHI. See
* [1] or SORCSD for details.
*
* P1, P2, Q1, and Q2 are represented as products of elementary
* reflectors. See SORCSD for details on generating P1, P2, Q1, and Q2
* using SORGQR and SORGLQ.
*
* Reference
* =========
*
* [1] Brian D. Sutton. Computing the complete CS decomposition. Numer.
* Algorithms, 50(1):33-65, 2009.
*
* ====================================================================
*
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sorcsd
USAGE:
theta, u1, u2, v1t, v2t, info = NumRu::Lapack.sorcsd( jobu1, jobu2, jobv1t, jobv2t, trans, signs, m, x11, x12, x21, x22, lwork, [:usage => usage, :help => help])
FORTRAN MANUAL
RECURSIVE SUBROUTINE SORCSD( JOBU1, JOBU2, JOBV1T, JOBV2T, TRANS, SIGNS, M, P, Q, X11, LDX11, X12, LDX12, X21, LDX21, X22, LDX22, THETA, U1, LDU1, U2, LDU2, V1T, LDV1T, V2T, LDV2T, WORK, LWORK, IWORK, INFO )
* Purpose
* =======
*
* SORCSD computes the CS decomposition of an M-by-M partitioned
* orthogonal matrix X:
*
* [ I 0 0 | 0 0 0 ]
* [ 0 C 0 | 0 -S 0 ]
* [ X11 | X12 ] [ U1 | ] [ 0 0 0 | 0 0 -I ] [ V1 | ]**T
* X = [-----------] = [---------] [---------------------] [---------] .
* [ X21 | X22 ] [ | U2 ] [ 0 0 0 | I 0 0 ] [ | V2 ]
* [ 0 S 0 | 0 C 0 ]
* [ 0 0 I | 0 0 0 ]
*
* X11 is P-by-Q. The orthogonal matrices U1, U2, V1, and V2 are P-by-P,
* (M-P)-by-(M-P), Q-by-Q, and (M-Q)-by-(M-Q), respectively. C and S are
* R-by-R nonnegative diagonal matrices satisfying C^2 + S^2 = I, in
* which R = MIN(P,M-P,Q,M-Q).
*
* Arguments
* =========
*
* JOBU1 (input) CHARACTER
* = 'Y': U1 is computed;
* otherwise: U1 is not computed.
*
* JOBU2 (input) CHARACTER
* = 'Y': U2 is computed;
* otherwise: U2 is not computed.
*
* JOBV1T (input) CHARACTER
* = 'Y': V1T is computed;
* otherwise: V1T is not computed.
*
* JOBV2T (input) CHARACTER
* = 'Y': V2T is computed;
* otherwise: V2T is not computed.
*
* TRANS (input) CHARACTER
* = 'T': X, U1, U2, V1T, and V2T are stored in row-major
* order;
* otherwise: X, U1, U2, V1T, and V2T are stored in column-
* major order.
*
* SIGNS (input) CHARACTER
* = 'O': The lower-left block is made nonpositive (the
* "other" convention);
* otherwise: The upper-right block is made nonpositive (the
* "default" convention).
*
* M (input) INTEGER
* The number of rows and columns in X.
*
* P (input) INTEGER
* The number of rows in X11 and X12. 0 <= P <= M.
*
* Q (input) INTEGER
* The number of columns in X11 and X21. 0 <= Q <= M.
*
* X (input/workspace) REAL array, dimension (LDX,M)
* On entry, the orthogonal matrix whose CSD is desired.
*
* LDX (input) INTEGER
* The leading dimension of X. LDX >= MAX(1,M).
*
* THETA (output) REAL array, dimension (R), in which R =
* MIN(P,M-P,Q,M-Q).
* C = DIAG( COS(THETA(1)), ... , COS(THETA(R)) ) and
* S = DIAG( SIN(THETA(1)), ... , SIN(THETA(R)) ).
*
* U1 (output) REAL array, dimension (P)
* If JOBU1 = 'Y', U1 contains the P-by-P orthogonal matrix U1.
*
* LDU1 (input) INTEGER
* The leading dimension of U1. If JOBU1 = 'Y', LDU1 >=
* MAX(1,P).
*
* U2 (output) REAL array, dimension (M-P)
* If JOBU2 = 'Y', U2 contains the (M-P)-by-(M-P) orthogonal
* matrix U2.
*
* LDU2 (input) INTEGER
* The leading dimension of U2. If JOBU2 = 'Y', LDU2 >=
* MAX(1,M-P).
*
* V1T (output) REAL array, dimension (Q)
* If JOBV1T = 'Y', V1T contains the Q-by-Q matrix orthogonal
* matrix V1**T.
*
* LDV1T (input) INTEGER
* The leading dimension of V1T. If JOBV1T = 'Y', LDV1T >=
* MAX(1,Q).
*
* V2T (output) REAL array, dimension (M-Q)
* If JOBV2T = 'Y', V2T contains the (M-Q)-by-(M-Q) orthogonal
* matrix V2**T.
*
* LDV2T (input) INTEGER
* The leading dimension of V2T. If JOBV2T = 'Y', LDV2T >=
* MAX(1,M-Q).
*
* WORK (workspace) REAL array, dimension (MAX(1,LWORK))
* On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
* If INFO > 0 on exit, WORK(2:R) contains the values PHI(1),
* ..., PHI(R-1) that, together with THETA(1), ..., THETA(R),
* define the matrix in intermediate bidiagonal-block form
* remaining after nonconvergence. INFO specifies the number
* of nonzero PHI's.
*
* LWORK (input) INTEGER
* The dimension of the array WORK.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the work array, and no error
* message related to LWORK is issued by XERBLA.
*
* IWORK (workspace) INTEGER array, dimension (M-Q)
*
* INFO (output) INTEGER
* = 0: successful exit.
* < 0: if INFO = -i, the i-th argument had an illegal value.
* > 0: SBBCSD did not converge. See the description of WORK
* above for details.
*
* Reference
* =========
*
* [1] Brian D. Sutton. Computing the complete CS decomposition. Numer.
* Algorithms, 50(1):33-65, 2009.
*
* ===================================================================
*
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sorg2l
USAGE:
info, a = NumRu::Lapack.sorg2l( m, a, tau, [:usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORG2L( M, N, K, A, LDA, TAU, WORK, INFO )
* Purpose
* =======
*
* SORG2L generates an m by n real 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 SGEQLF.
*
* Arguments
* =========
*
* M (input) INTEGER
* The number of rows of the matrix Q. M >= 0.
*
* N (input) INTEGER
* The number of columns of the matrix Q. M >= N >= 0.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines the
* matrix Q. N >= K >= 0.
*
* A (input/output) REAL array, dimension (LDA,N)
* 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 SGEQLF in the last k columns of its array
* argument A.
* On exit, the m by n matrix Q.
*
* LDA (input) INTEGER
* The first dimension of the array A. LDA >= max(1,M).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGEQLF.
*
* WORK (workspace) REAL array, dimension (N)
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument has an illegal value
*
* =====================================================================
*
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sorg2r
USAGE:
info, a = NumRu::Lapack.sorg2r( m, a, tau, [:usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORG2R( M, N, K, A, LDA, TAU, WORK, INFO )
* Purpose
* =======
*
* SORG2R generates an m by n real matrix Q with orthonormal columns,
* which is defined as the first n columns of a product of k elementary
* reflectors of order m
*
* Q = H(1) H(2) . . . H(k)
*
* as returned by SGEQRF.
*
* Arguments
* =========
*
* M (input) INTEGER
* The number of rows of the matrix Q. M >= 0.
*
* N (input) INTEGER
* The number of columns of the matrix Q. M >= N >= 0.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines the
* matrix Q. N >= K >= 0.
*
* A (input/output) REAL array, dimension (LDA,N)
* On entry, the i-th column must contain the vector which
* defines the elementary reflector H(i), for i = 1,2,...,k, as
* returned by SGEQRF in the first k columns of its array
* argument A.
* On exit, the m-by-n matrix Q.
*
* LDA (input) INTEGER
* The first dimension of the array A. LDA >= max(1,M).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGEQRF.
*
* WORK (workspace) REAL array, dimension (N)
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument has an illegal value
*
* =====================================================================
*
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sorgbr
USAGE:
work, info, a = NumRu::Lapack.sorgbr( vect, m, k, a, tau, [:lwork => lwork, :usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORGBR( VECT, M, N, K, A, LDA, TAU, WORK, LWORK, INFO )
* Purpose
* =======
*
* SORGBR generates one of the real orthogonal matrices Q or P**T
* determined by SGEBRD when reducing a real matrix A to bidiagonal
* form: A = Q * B * P**T. Q and P**T are defined as products of
* elementary reflectors H(i) or G(i) respectively.
*
* If VECT = 'Q', A is assumed to have been an M-by-K matrix, and Q
* is of order M:
* if m >= k, Q = H(1) H(2) . . . H(k) and SORGBR returns the first n
* columns of Q, where m >= n >= k;
* if m < k, Q = H(1) H(2) . . . H(m-1) and SORGBR returns Q as an
* M-by-M matrix.
*
* If VECT = 'P', A is assumed to have been a K-by-N matrix, and P**T
* is of order N:
* if k < n, P**T = G(k) . . . G(2) G(1) and SORGBR returns the first m
* rows of P**T, where n >= m >= k;
* if k >= n, P**T = G(n-1) . . . G(2) G(1) and SORGBR returns P**T as
* an N-by-N matrix.
*
* Arguments
* =========
*
* VECT (input) CHARACTER*1
* Specifies whether the matrix Q or the matrix P**T is
* required, as defined in the transformation applied by SGEBRD:
* = 'Q': generate Q;
* = 'P': generate P**T.
*
* M (input) INTEGER
* The number of rows of the matrix Q or P**T to be returned.
* M >= 0.
*
* N (input) INTEGER
* The number of columns of the matrix Q or P**T to be returned.
* N >= 0.
* If VECT = 'Q', M >= N >= min(M,K);
* if VECT = 'P', N >= M >= min(N,K).
*
* K (input) INTEGER
* If VECT = 'Q', the number of columns in the original M-by-K
* matrix reduced by SGEBRD.
* If VECT = 'P', the number of rows in the original K-by-N
* matrix reduced by SGEBRD.
* K >= 0.
*
* A (input/output) REAL array, dimension (LDA,N)
* On entry, the vectors which define the elementary reflectors,
* as returned by SGEBRD.
* On exit, the M-by-N matrix Q or P**T.
*
* LDA (input) INTEGER
* The leading dimension of the array A. LDA >= max(1,M).
*
* TAU (input) REAL array, dimension
* (min(M,K)) if VECT = 'Q'
* (min(N,K)) if VECT = 'P'
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i) or G(i), which determines Q or P**T, as
* returned by SGEBRD in its array argument TAUQ or TAUP.
*
* WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
* On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
*
* LWORK (input) INTEGER
* The dimension of the array WORK. LWORK >= max(1,min(M,N)).
* For optimum performance LWORK >= min(M,N)*NB, where NB
* is the optimal blocksize.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the WORK array, and no error
* message related to LWORK is issued by XERBLA.
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument had an illegal value
*
* =====================================================================
*
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sorghr
USAGE:
work, info, a = NumRu::Lapack.sorghr( ilo, ihi, a, tau, [:lwork => lwork, :usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORGHR( N, ILO, IHI, A, LDA, TAU, WORK, LWORK, INFO )
* Purpose
* =======
*
* SORGHR generates a real orthogonal matrix Q which is defined as the
* product of IHI-ILO elementary reflectors of order N, as returned by
* SGEHRD:
*
* Q = H(ilo) H(ilo+1) . . . H(ihi-1).
*
* Arguments
* =========
*
* N (input) INTEGER
* The order of the matrix Q. N >= 0.
*
* ILO (input) INTEGER
* IHI (input) INTEGER
* ILO and IHI must have the same values as in the previous call
* of SGEHRD. Q is equal to the unit matrix except in the
* submatrix Q(ilo+1:ihi,ilo+1:ihi).
* 1 <= ILO <= IHI <= N, if N > 0; ILO=1 and IHI=0, if N=0.
*
* A (input/output) REAL array, dimension (LDA,N)
* On entry, the vectors which define the elementary reflectors,
* as returned by SGEHRD.
* On exit, the N-by-N orthogonal matrix Q.
*
* LDA (input) INTEGER
* The leading dimension of the array A. LDA >= max(1,N).
*
* TAU (input) REAL array, dimension (N-1)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGEHRD.
*
* WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
* On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
*
* LWORK (input) INTEGER
* The dimension of the array WORK. LWORK >= IHI-ILO.
* For optimum performance LWORK >= (IHI-ILO)*NB, where NB is
* the optimal blocksize.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the WORK array, and no error
* message related to LWORK is issued by XERBLA.
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument had an illegal value
*
* =====================================================================
*
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sorgl2
USAGE:
info, a = NumRu::Lapack.sorgl2( a, tau, [:usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORGL2( M, N, K, A, LDA, TAU, WORK, INFO )
* Purpose
* =======
*
* SORGL2 generates an m by n real matrix Q with orthonormal rows,
* which is defined as the first m rows of a product of k elementary
* reflectors of order n
*
* Q = H(k) . . . H(2) H(1)
*
* as returned by SGELQF.
*
* Arguments
* =========
*
* M (input) INTEGER
* The number of rows of the matrix Q. M >= 0.
*
* N (input) INTEGER
* The number of columns of the matrix Q. N >= M.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines the
* matrix Q. M >= K >= 0.
*
* A (input/output) REAL array, dimension (LDA,N)
* On entry, the i-th row must contain the vector which defines
* the elementary reflector H(i), for i = 1,2,...,k, as returned
* by SGELQF in the first k rows of its array argument A.
* On exit, the m-by-n matrix Q.
*
* LDA (input) INTEGER
* The first dimension of the array A. LDA >= max(1,M).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGELQF.
*
* WORK (workspace) REAL array, dimension (M)
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument has an illegal value
*
* =====================================================================
*
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sorglq
USAGE:
work, info, a = NumRu::Lapack.sorglq( m, a, tau, [:lwork => lwork, :usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORGLQ( M, N, K, A, LDA, TAU, WORK, LWORK, INFO )
* Purpose
* =======
*
* SORGLQ generates an M-by-N real matrix Q with orthonormal rows,
* which is defined as the first M rows of a product of K elementary
* reflectors of order N
*
* Q = H(k) . . . H(2) H(1)
*
* as returned by SGELQF.
*
* Arguments
* =========
*
* M (input) INTEGER
* The number of rows of the matrix Q. M >= 0.
*
* N (input) INTEGER
* The number of columns of the matrix Q. N >= M.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines the
* matrix Q. M >= K >= 0.
*
* A (input/output) REAL array, dimension (LDA,N)
* On entry, the i-th row must contain the vector which defines
* the elementary reflector H(i), for i = 1,2,...,k, as returned
* by SGELQF in the first k rows of its array argument A.
* On exit, the M-by-N matrix Q.
*
* LDA (input) INTEGER
* The first dimension of the array A. LDA >= max(1,M).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGELQF.
*
* WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
* On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
*
* LWORK (input) INTEGER
* The dimension of the array WORK. LWORK >= max(1,M).
* For optimum performance LWORK >= M*NB, where NB is
* the optimal blocksize.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the WORK array, and no error
* message related to LWORK is issued by XERBLA.
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument has an illegal value
*
* =====================================================================
*
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sorgql
USAGE:
work, info, a = NumRu::Lapack.sorgql( m, a, tau, [:lwork => lwork, :usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORGQL( M, N, K, A, LDA, TAU, WORK, LWORK, INFO )
* Purpose
* =======
*
* SORGQL generates an M-by-N real 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 SGEQLF.
*
* Arguments
* =========
*
* M (input) INTEGER
* The number of rows of the matrix Q. M >= 0.
*
* N (input) INTEGER
* The number of columns of the matrix Q. M >= N >= 0.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines the
* matrix Q. N >= K >= 0.
*
* A (input/output) REAL array, dimension (LDA,N)
* 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 SGEQLF in the last k columns of its array
* argument A.
* On exit, the M-by-N matrix Q.
*
* LDA (input) INTEGER
* The first dimension of the array A. LDA >= max(1,M).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGEQLF.
*
* WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
* On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
*
* LWORK (input) INTEGER
* The dimension of the array WORK. LWORK >= max(1,N).
* For optimum performance LWORK >= N*NB, where NB is the
* optimal blocksize.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the WORK array, and no error
* message related to LWORK is issued by XERBLA.
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument has an illegal value
*
* =====================================================================
*
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sorgqr
USAGE:
work, info, a = NumRu::Lapack.sorgqr( m, a, tau, [:lwork => lwork, :usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORGQR( M, N, K, A, LDA, TAU, WORK, LWORK, INFO )
* Purpose
* =======
*
* SORGQR generates an M-by-N real matrix Q with orthonormal columns,
* which is defined as the first N columns of a product of K elementary
* reflectors of order M
*
* Q = H(1) H(2) . . . H(k)
*
* as returned by SGEQRF.
*
* Arguments
* =========
*
* M (input) INTEGER
* The number of rows of the matrix Q. M >= 0.
*
* N (input) INTEGER
* The number of columns of the matrix Q. M >= N >= 0.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines the
* matrix Q. N >= K >= 0.
*
* A (input/output) REAL array, dimension (LDA,N)
* On entry, the i-th column must contain the vector which
* defines the elementary reflector H(i), for i = 1,2,...,k, as
* returned by SGEQRF in the first k columns of its array
* argument A.
* On exit, the M-by-N matrix Q.
*
* LDA (input) INTEGER
* The first dimension of the array A. LDA >= max(1,M).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGEQRF.
*
* WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
* On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
*
* LWORK (input) INTEGER
* The dimension of the array WORK. LWORK >= max(1,N).
* For optimum performance LWORK >= N*NB, where NB is the
* optimal blocksize.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the WORK array, and no error
* message related to LWORK is issued by XERBLA.
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument has an illegal value
*
* =====================================================================
*
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sorgr2
USAGE:
info, a = NumRu::Lapack.sorgr2( a, tau, [:usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORGR2( M, N, K, A, LDA, TAU, WORK, INFO )
* Purpose
* =======
*
* SORGR2 generates an m by n real matrix Q with orthonormal rows,
* which is defined as the last m rows of a product of k elementary
* reflectors of order n
*
* Q = H(1) H(2) . . . H(k)
*
* as returned by SGERQF.
*
* Arguments
* =========
*
* M (input) INTEGER
* The number of rows of the matrix Q. M >= 0.
*
* N (input) INTEGER
* The number of columns of the matrix Q. N >= M.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines the
* matrix Q. M >= K >= 0.
*
* A (input/output) REAL array, dimension (LDA,N)
* On entry, the (m-k+i)-th row must contain the vector which
* defines the elementary reflector H(i), for i = 1,2,...,k, as
* returned by SGERQF in the last k rows of its array argument
* A.
* On exit, the m by n matrix Q.
*
* LDA (input) INTEGER
* The first dimension of the array A. LDA >= max(1,M).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGERQF.
*
* WORK (workspace) REAL array, dimension (M)
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument has an illegal value
*
* =====================================================================
*
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sorgrq
USAGE:
work, info, a = NumRu::Lapack.sorgrq( m, a, tau, [:lwork => lwork, :usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORGRQ( M, N, K, A, LDA, TAU, WORK, LWORK, INFO )
* Purpose
* =======
*
* SORGRQ generates an M-by-N real matrix Q with orthonormal rows,
* which is defined as the last M rows of a product of K elementary
* reflectors of order N
*
* Q = H(1) H(2) . . . H(k)
*
* as returned by SGERQF.
*
* Arguments
* =========
*
* M (input) INTEGER
* The number of rows of the matrix Q. M >= 0.
*
* N (input) INTEGER
* The number of columns of the matrix Q. N >= M.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines the
* matrix Q. M >= K >= 0.
*
* A (input/output) REAL array, dimension (LDA,N)
* On entry, the (m-k+i)-th row must contain the vector which
* defines the elementary reflector H(i), for i = 1,2,...,k, as
* returned by SGERQF in the last k rows of its array argument
* A.
* On exit, the M-by-N matrix Q.
*
* LDA (input) INTEGER
* The first dimension of the array A. LDA >= max(1,M).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGERQF.
*
* WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
* On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
*
* LWORK (input) INTEGER
* The dimension of the array WORK. LWORK >= max(1,M).
* For optimum performance LWORK >= M*NB, where NB is the
* optimal blocksize.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the WORK array, and no error
* message related to LWORK is issued by XERBLA.
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument has an illegal value
*
* =====================================================================
*
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sorgtr
USAGE:
work, info, a = NumRu::Lapack.sorgtr( uplo, a, tau, [:lwork => lwork, :usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORGTR( UPLO, N, A, LDA, TAU, WORK, LWORK, INFO )
* Purpose
* =======
*
* SORGTR generates a real orthogonal matrix Q which is defined as the
* product of n-1 elementary reflectors of order N, as returned by
* SSYTRD:
*
* 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 triangle of A contains elementary reflectors
* from SSYTRD;
* = 'L': Lower triangle of A contains elementary reflectors
* from SSYTRD.
*
* N (input) INTEGER
* The order of the matrix Q. N >= 0.
*
* A (input/output) REAL array, dimension (LDA,N)
* On entry, the vectors which define the elementary reflectors,
* as returned by SSYTRD.
* On exit, the N-by-N orthogonal matrix Q.
*
* LDA (input) INTEGER
* The leading dimension of the array A. LDA >= max(1,N).
*
* TAU (input) REAL array, dimension (N-1)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SSYTRD.
*
* WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
* On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
*
* LWORK (input) INTEGER
* The dimension of the array WORK. LWORK >= max(1,N-1).
* For optimum performance LWORK >= (N-1)*NB, where NB is
* the optimal blocksize.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the WORK array, and no error
* message related to LWORK is issued by XERBLA.
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument had an illegal value
*
* =====================================================================
*
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sorm2l
USAGE:
info, c = NumRu::Lapack.sorm2l( side, trans, m, a, tau, c, [:usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORM2L( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK, INFO )
* Purpose
* =======
*
* SORM2L overwrites the general real m by n matrix C with
*
* Q * C if SIDE = 'L' and TRANS = 'N', or
*
* Q'* C if SIDE = 'L' and TRANS = 'T', or
*
* C * Q if SIDE = 'R' and TRANS = 'N', or
*
* C * Q' if SIDE = 'R' and TRANS = 'T',
*
* where Q is a real orthogonal matrix defined as the product of k
* elementary reflectors
*
* Q = H(k) . . . H(2) H(1)
*
* as returned by SGEQLF. Q is of order m if SIDE = 'L' and of order n
* if SIDE = 'R'.
*
* Arguments
* =========
*
* SIDE (input) CHARACTER*1
* = 'L': apply Q or Q' from the Left
* = 'R': apply Q or Q' from the Right
*
* TRANS (input) CHARACTER*1
* = 'N': apply Q (No transpose)
* = 'T': apply Q' (Transpose)
*
* 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.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines
* the matrix Q.
* If SIDE = 'L', M >= K >= 0;
* if SIDE = 'R', N >= K >= 0.
*
* A (input) REAL array, dimension (LDA,K)
* The i-th column must contain the vector which defines the
* elementary reflector H(i), for i = 1,2,...,k, as returned by
* SGEQLF in the last k columns of its array argument A.
* A is modified by the routine but restored on exit.
*
* LDA (input) INTEGER
* The leading dimension of the array A.
* If SIDE = 'L', LDA >= max(1,M);
* if SIDE = 'R', LDA >= max(1,N).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGEQLF.
*
* C (input/output) REAL array, dimension (LDC,N)
* On entry, the m by n matrix C.
* On exit, C is overwritten by Q*C or Q'*C or C*Q' or C*Q.
*
* LDC (input) INTEGER
* The leading dimension of the array C. LDC >= max(1,M).
*
* WORK (workspace) REAL 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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sorm2r
USAGE:
info, c = NumRu::Lapack.sorm2r( side, trans, m, a, tau, c, [:usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORM2R( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK, INFO )
* Purpose
* =======
*
* SORM2R overwrites the general real m by n matrix C with
*
* Q * C if SIDE = 'L' and TRANS = 'N', or
*
* Q'* C if SIDE = 'L' and TRANS = 'T', or
*
* C * Q if SIDE = 'R' and TRANS = 'N', or
*
* C * Q' if SIDE = 'R' and TRANS = 'T',
*
* where Q is a real orthogonal matrix defined as the product of k
* elementary reflectors
*
* Q = H(1) H(2) . . . H(k)
*
* as returned by SGEQRF. Q is of order m if SIDE = 'L' and of order n
* if SIDE = 'R'.
*
* Arguments
* =========
*
* SIDE (input) CHARACTER*1
* = 'L': apply Q or Q' from the Left
* = 'R': apply Q or Q' from the Right
*
* TRANS (input) CHARACTER*1
* = 'N': apply Q (No transpose)
* = 'T': apply Q' (Transpose)
*
* 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.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines
* the matrix Q.
* If SIDE = 'L', M >= K >= 0;
* if SIDE = 'R', N >= K >= 0.
*
* A (input) REAL array, dimension (LDA,K)
* The i-th column must contain the vector which defines the
* elementary reflector H(i), for i = 1,2,...,k, as returned by
* SGEQRF in the first k columns of its array argument A.
* A is modified by the routine but restored on exit.
*
* LDA (input) INTEGER
* The leading dimension of the array A.
* If SIDE = 'L', LDA >= max(1,M);
* if SIDE = 'R', LDA >= max(1,N).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGEQRF.
*
* C (input/output) REAL array, dimension (LDC,N)
* On entry, the m by n matrix C.
* On exit, C is overwritten by Q*C or Q'*C or C*Q' or C*Q.
*
* LDC (input) INTEGER
* The leading dimension of the array C. LDC >= max(1,M).
*
* WORK (workspace) REAL 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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sormbr
USAGE:
work, info, c = NumRu::Lapack.sormbr( vect, side, trans, m, k, a, tau, c, [:lwork => lwork, :usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORMBR( VECT, SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK, LWORK, INFO )
* Purpose
* =======
*
* If VECT = 'Q', SORMBR overwrites the general real M-by-N matrix C
* with
* SIDE = 'L' SIDE = 'R'
* TRANS = 'N': Q * C C * Q
* TRANS = 'T': Q**T * C C * Q**T
*
* If VECT = 'P', SORMBR overwrites the general real M-by-N matrix C
* with
* SIDE = 'L' SIDE = 'R'
* TRANS = 'N': P * C C * P
* TRANS = 'T': P**T * C C * P**T
*
* Here Q and P**T are the orthogonal matrices determined by SGEBRD when
* reducing a real matrix A to bidiagonal form: A = Q * B * P**T. Q and
* P**T are defined as products of elementary reflectors H(i) and G(i)
* respectively.
*
* Let nq = m if SIDE = 'L' and nq = n if SIDE = 'R'. Thus nq is the
* order of the orthogonal matrix Q or P**T that is applied.
*
* If VECT = 'Q', A is assumed to have been an NQ-by-K matrix:
* if nq >= k, Q = H(1) H(2) . . . H(k);
* if nq < k, Q = H(1) H(2) . . . H(nq-1).
*
* If VECT = 'P', A is assumed to have been a K-by-NQ matrix:
* if k < nq, P = G(1) G(2) . . . G(k);
* if k >= nq, P = G(1) G(2) . . . G(nq-1).
*
* Arguments
* =========
*
* VECT (input) CHARACTER*1
* = 'Q': apply Q or Q**T;
* = 'P': apply P or P**T.
*
* SIDE (input) CHARACTER*1
* = 'L': apply Q, Q**T, P or P**T from the Left;
* = 'R': apply Q, Q**T, P or P**T from the Right.
*
* TRANS (input) CHARACTER*1
* = 'N': No transpose, apply Q or P;
* = 'T': Transpose, apply Q**T or P**T.
*
* 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.
*
* K (input) INTEGER
* If VECT = 'Q', the number of columns in the original
* matrix reduced by SGEBRD.
* If VECT = 'P', the number of rows in the original
* matrix reduced by SGEBRD.
* K >= 0.
*
* A (input) REAL array, dimension
* (LDA,min(nq,K)) if VECT = 'Q'
* (LDA,nq) if VECT = 'P'
* The vectors which define the elementary reflectors H(i) and
* G(i), whose products determine the matrices Q and P, as
* returned by SGEBRD.
*
* LDA (input) INTEGER
* The leading dimension of the array A.
* If VECT = 'Q', LDA >= max(1,nq);
* if VECT = 'P', LDA >= max(1,min(nq,K)).
*
* TAU (input) REAL array, dimension (min(nq,K))
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i) or G(i) which determines Q or P, as returned
* by SGEBRD in the array argument TAUQ or TAUP.
*
* C (input/output) REAL array, dimension (LDC,N)
* On entry, the M-by-N matrix C.
* On exit, C is overwritten by Q*C or Q**T*C or C*Q**T or C*Q
* or P*C or P**T*C or C*P or C*P**T.
*
* LDC (input) INTEGER
* The leading dimension of the array C. LDC >= max(1,M).
*
* WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
* On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
*
* LWORK (input) INTEGER
* The dimension of the array WORK.
* If SIDE = 'L', LWORK >= max(1,N);
* if SIDE = 'R', LWORK >= max(1,M).
* For optimum performance LWORK >= N*NB if SIDE = 'L', and
* LWORK >= M*NB if SIDE = 'R', where NB is the optimal
* blocksize.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the WORK array, and no error
* message related to LWORK is issued by XERBLA.
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument had an illegal value
*
* =====================================================================
*
* .. Local Scalars ..
LOGICAL APPLYQ, LEFT, LQUERY, NOTRAN
CHARACTER TRANST
INTEGER I1, I2, IINFO, LWKOPT, MI, NB, NI, NQ, NW
* ..
* .. External Functions ..
LOGICAL LSAME
INTEGER ILAENV
EXTERNAL ILAENV, LSAME
* ..
* .. External Subroutines ..
EXTERNAL SORMLQ, SORMQR, XERBLA
* ..
* .. Intrinsic Functions ..
INTRINSIC MAX, MIN
* ..
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sormhr
USAGE:
work, info, c = NumRu::Lapack.sormhr( side, trans, ilo, ihi, a, tau, c, [:lwork => lwork, :usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORMHR( SIDE, TRANS, M, N, ILO, IHI, A, LDA, TAU, C, LDC, WORK, LWORK, INFO )
* Purpose
* =======
*
* SORMHR overwrites the general real M-by-N matrix C with
*
* SIDE = 'L' SIDE = 'R'
* TRANS = 'N': Q * C C * Q
* TRANS = 'T': Q**T * C C * Q**T
*
* where Q is a real orthogonal matrix of order nq, with nq = m if
* SIDE = 'L' and nq = n if SIDE = 'R'. Q is defined as the product of
* IHI-ILO elementary reflectors, as returned by SGEHRD:
*
* Q = H(ilo) H(ilo+1) . . . H(ihi-1).
*
* Arguments
* =========
*
* SIDE (input) CHARACTER*1
* = 'L': apply Q or Q**T from the Left;
* = 'R': apply Q or Q**T from the Right.
*
* TRANS (input) CHARACTER*1
* = 'N': No transpose, apply Q;
* = 'T': Transpose, apply Q**T.
*
* 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.
*
* ILO (input) INTEGER
* IHI (input) INTEGER
* ILO and IHI must have the same values as in the previous call
* of SGEHRD. Q is equal to the unit matrix except in the
* submatrix Q(ilo+1:ihi,ilo+1:ihi).
* If SIDE = 'L', then 1 <= ILO <= IHI <= M, if M > 0, and
* ILO = 1 and IHI = 0, if M = 0;
* if SIDE = 'R', then 1 <= ILO <= IHI <= N, if N > 0, and
* ILO = 1 and IHI = 0, if N = 0.
*
* A (input) REAL array, dimension
* (LDA,M) if SIDE = 'L'
* (LDA,N) if SIDE = 'R'
* The vectors which define the elementary reflectors, as
* returned by SGEHRD.
*
* LDA (input) INTEGER
* The leading dimension of the array A.
* LDA >= max(1,M) if SIDE = 'L'; LDA >= max(1,N) if SIDE = 'R'.
*
* TAU (input) REAL array, dimension
* (M-1) if SIDE = 'L'
* (N-1) if SIDE = 'R'
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGEHRD.
*
* C (input/output) REAL array, dimension (LDC,N)
* On entry, the M-by-N matrix C.
* On exit, C is overwritten by Q*C or Q**T*C or C*Q**T or C*Q.
*
* LDC (input) INTEGER
* The leading dimension of the array C. LDC >= max(1,M).
*
* WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
* On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
*
* LWORK (input) INTEGER
* The dimension of the array WORK.
* If SIDE = 'L', LWORK >= max(1,N);
* if SIDE = 'R', LWORK >= max(1,M).
* For optimum performance LWORK >= N*NB if SIDE = 'L', and
* LWORK >= M*NB if SIDE = 'R', where NB is the optimal
* blocksize.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the WORK array, and no error
* message related to LWORK is issued by XERBLA.
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument had an illegal value
*
* =====================================================================
*
* .. Local Scalars ..
LOGICAL LEFT, LQUERY
INTEGER I1, I2, IINFO, LWKOPT, MI, NB, NH, NI, NQ, NW
* ..
* .. External Functions ..
LOGICAL LSAME
INTEGER ILAENV
EXTERNAL ILAENV, LSAME
* ..
* .. External Subroutines ..
EXTERNAL SORMQR, XERBLA
* ..
* .. Intrinsic Functions ..
INTRINSIC MAX, MIN
* ..
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sorml2
USAGE:
info, c = NumRu::Lapack.sorml2( side, trans, a, tau, c, [:usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORML2( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK, INFO )
* Purpose
* =======
*
* SORML2 overwrites the general real m by n matrix C with
*
* Q * C if SIDE = 'L' and TRANS = 'N', or
*
* Q'* C if SIDE = 'L' and TRANS = 'T', or
*
* C * Q if SIDE = 'R' and TRANS = 'N', or
*
* C * Q' if SIDE = 'R' and TRANS = 'T',
*
* where Q is a real orthogonal matrix defined as the product of k
* elementary reflectors
*
* Q = H(k) . . . H(2) H(1)
*
* as returned by SGELQF. Q is of order m if SIDE = 'L' and of order n
* if SIDE = 'R'.
*
* Arguments
* =========
*
* SIDE (input) CHARACTER*1
* = 'L': apply Q or Q' from the Left
* = 'R': apply Q or Q' from the Right
*
* TRANS (input) CHARACTER*1
* = 'N': apply Q (No transpose)
* = 'T': apply Q' (Transpose)
*
* 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.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines
* the matrix Q.
* If SIDE = 'L', M >= K >= 0;
* if SIDE = 'R', N >= K >= 0.
*
* A (input) REAL array, dimension
* (LDA,M) if SIDE = 'L',
* (LDA,N) if SIDE = 'R'
* The i-th row must contain the vector which defines the
* elementary reflector H(i), for i = 1,2,...,k, as returned by
* SGELQF in the first k rows of its array argument A.
* A is modified by the routine but restored on exit.
*
* LDA (input) INTEGER
* The leading dimension of the array A. LDA >= max(1,K).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGELQF.
*
* C (input/output) REAL array, dimension (LDC,N)
* On entry, the m by n matrix C.
* On exit, C is overwritten by Q*C or Q'*C or C*Q' or C*Q.
*
* LDC (input) INTEGER
* The leading dimension of the array C. LDC >= max(1,M).
*
* WORK (workspace) REAL 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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sormlq
USAGE:
work, info, c = NumRu::Lapack.sormlq( side, trans, a, tau, c, [:lwork => lwork, :usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORMLQ( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK, LWORK, INFO )
* Purpose
* =======
*
* SORMLQ overwrites the general real M-by-N matrix C with
*
* SIDE = 'L' SIDE = 'R'
* TRANS = 'N': Q * C C * Q
* TRANS = 'T': Q**T * C C * Q**T
*
* where Q is a real orthogonal matrix defined as the product of k
* elementary reflectors
*
* Q = H(k) . . . H(2) H(1)
*
* as returned by SGELQF. Q is of order M if SIDE = 'L' and of order N
* if SIDE = 'R'.
*
* Arguments
* =========
*
* SIDE (input) CHARACTER*1
* = 'L': apply Q or Q**T from the Left;
* = 'R': apply Q or Q**T from the Right.
*
* TRANS (input) CHARACTER*1
* = 'N': No transpose, apply Q;
* = 'T': Transpose, apply Q**T.
*
* 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.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines
* the matrix Q.
* If SIDE = 'L', M >= K >= 0;
* if SIDE = 'R', N >= K >= 0.
*
* A (input) REAL array, dimension
* (LDA,M) if SIDE = 'L',
* (LDA,N) if SIDE = 'R'
* The i-th row must contain the vector which defines the
* elementary reflector H(i), for i = 1,2,...,k, as returned by
* SGELQF in the first k rows of its array argument A.
* A is modified by the routine but restored on exit.
*
* LDA (input) INTEGER
* The leading dimension of the array A. LDA >= max(1,K).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGELQF.
*
* C (input/output) REAL array, dimension (LDC,N)
* On entry, the M-by-N matrix C.
* On exit, C is overwritten by Q*C or Q**T*C or C*Q**T or C*Q.
*
* LDC (input) INTEGER
* The leading dimension of the array C. LDC >= max(1,M).
*
* WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
* On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
*
* LWORK (input) INTEGER
* The dimension of the array WORK.
* If SIDE = 'L', LWORK >= max(1,N);
* if SIDE = 'R', LWORK >= max(1,M).
* For optimum performance LWORK >= N*NB if SIDE = 'L', and
* LWORK >= M*NB if SIDE = 'R', where NB is the optimal
* blocksize.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the WORK array, and no error
* message related to LWORK is issued by XERBLA.
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument had an illegal value
*
* =====================================================================
*
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sormql
USAGE:
work, info, c = NumRu::Lapack.sormql( side, trans, m, a, tau, c, [:lwork => lwork, :usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORMQL( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK, LWORK, INFO )
* Purpose
* =======
*
* SORMQL overwrites the general real M-by-N matrix C with
*
* SIDE = 'L' SIDE = 'R'
* TRANS = 'N': Q * C C * Q
* TRANS = 'T': Q**T * C C * Q**T
*
* where Q is a real orthogonal matrix defined as the product of k
* elementary reflectors
*
* Q = H(k) . . . H(2) H(1)
*
* as returned by SGEQLF. Q is of order M if SIDE = 'L' and of order N
* if SIDE = 'R'.
*
* Arguments
* =========
*
* SIDE (input) CHARACTER*1
* = 'L': apply Q or Q**T from the Left;
* = 'R': apply Q or Q**T from the Right.
*
* TRANS (input) CHARACTER*1
* = 'N': No transpose, apply Q;
* = 'T': Transpose, apply Q**T.
*
* 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.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines
* the matrix Q.
* If SIDE = 'L', M >= K >= 0;
* if SIDE = 'R', N >= K >= 0.
*
* A (input) REAL array, dimension (LDA,K)
* The i-th column must contain the vector which defines the
* elementary reflector H(i), for i = 1,2,...,k, as returned by
* SGEQLF in the last k columns of its array argument A.
* A is modified by the routine but restored on exit.
*
* LDA (input) INTEGER
* The leading dimension of the array A.
* If SIDE = 'L', LDA >= max(1,M);
* if SIDE = 'R', LDA >= max(1,N).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGEQLF.
*
* C (input/output) REAL array, dimension (LDC,N)
* On entry, the M-by-N matrix C.
* On exit, C is overwritten by Q*C or Q**T*C or C*Q**T or C*Q.
*
* LDC (input) INTEGER
* The leading dimension of the array C. LDC >= max(1,M).
*
* WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
* On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
*
* LWORK (input) INTEGER
* The dimension of the array WORK.
* If SIDE = 'L', LWORK >= max(1,N);
* if SIDE = 'R', LWORK >= max(1,M).
* For optimum performance LWORK >= N*NB if SIDE = 'L', and
* LWORK >= M*NB if SIDE = 'R', where NB is the optimal
* blocksize.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the WORK array, and no error
* message related to LWORK is issued by XERBLA.
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument had an illegal value
*
* =====================================================================
*
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sormqr
USAGE:
work, info, c = NumRu::Lapack.sormqr( side, trans, m, a, tau, c, [:lwork => lwork, :usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORMQR( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK, LWORK, INFO )
* Purpose
* =======
*
* SORMQR overwrites the general real M-by-N matrix C with
*
* SIDE = 'L' SIDE = 'R'
* TRANS = 'N': Q * C C * Q
* TRANS = 'T': Q**T * C C * Q**T
*
* where Q is a real orthogonal matrix defined as the product of k
* elementary reflectors
*
* Q = H(1) H(2) . . . H(k)
*
* as returned by SGEQRF. Q is of order M if SIDE = 'L' and of order N
* if SIDE = 'R'.
*
* Arguments
* =========
*
* SIDE (input) CHARACTER*1
* = 'L': apply Q or Q**T from the Left;
* = 'R': apply Q or Q**T from the Right.
*
* TRANS (input) CHARACTER*1
* = 'N': No transpose, apply Q;
* = 'T': Transpose, apply Q**T.
*
* 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.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines
* the matrix Q.
* If SIDE = 'L', M >= K >= 0;
* if SIDE = 'R', N >= K >= 0.
*
* A (input) REAL array, dimension (LDA,K)
* The i-th column must contain the vector which defines the
* elementary reflector H(i), for i = 1,2,...,k, as returned by
* SGEQRF in the first k columns of its array argument A.
* A is modified by the routine but restored on exit.
*
* LDA (input) INTEGER
* The leading dimension of the array A.
* If SIDE = 'L', LDA >= max(1,M);
* if SIDE = 'R', LDA >= max(1,N).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGEQRF.
*
* C (input/output) REAL array, dimension (LDC,N)
* On entry, the M-by-N matrix C.
* On exit, C is overwritten by Q*C or Q**T*C or C*Q**T or C*Q.
*
* LDC (input) INTEGER
* The leading dimension of the array C. LDC >= max(1,M).
*
* WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
* On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
*
* LWORK (input) INTEGER
* The dimension of the array WORK.
* If SIDE = 'L', LWORK >= max(1,N);
* if SIDE = 'R', LWORK >= max(1,M).
* For optimum performance LWORK >= N*NB if SIDE = 'L', and
* LWORK >= M*NB if SIDE = 'R', where NB is the optimal
* blocksize.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the WORK array, and no error
* message related to LWORK is issued by XERBLA.
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument had an illegal value
*
* =====================================================================
*
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sormr2
USAGE:
info, c = NumRu::Lapack.sormr2( side, trans, a, tau, c, [:usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORMR2( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK, INFO )
* Purpose
* =======
*
* SORMR2 overwrites the general real m by n matrix C with
*
* Q * C if SIDE = 'L' and TRANS = 'N', or
*
* Q'* C if SIDE = 'L' and TRANS = 'T', or
*
* C * Q if SIDE = 'R' and TRANS = 'N', or
*
* C * Q' if SIDE = 'R' and TRANS = 'T',
*
* where Q is a real orthogonal matrix defined as the product of k
* elementary reflectors
*
* Q = H(1) H(2) . . . H(k)
*
* as returned by SGERQF. Q is of order m if SIDE = 'L' and of order n
* if SIDE = 'R'.
*
* Arguments
* =========
*
* SIDE (input) CHARACTER*1
* = 'L': apply Q or Q' from the Left
* = 'R': apply Q or Q' from the Right
*
* TRANS (input) CHARACTER*1
* = 'N': apply Q (No transpose)
* = 'T': apply Q' (Transpose)
*
* 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.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines
* the matrix Q.
* If SIDE = 'L', M >= K >= 0;
* if SIDE = 'R', N >= K >= 0.
*
* A (input) REAL array, dimension
* (LDA,M) if SIDE = 'L',
* (LDA,N) if SIDE = 'R'
* The i-th row must contain the vector which defines the
* elementary reflector H(i), for i = 1,2,...,k, as returned by
* SGERQF in the last k rows of its array argument A.
* A is modified by the routine but restored on exit.
*
* LDA (input) INTEGER
* The leading dimension of the array A. LDA >= max(1,K).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGERQF.
*
* C (input/output) REAL array, dimension (LDC,N)
* On entry, the m by n matrix C.
* On exit, C is overwritten by Q*C or Q'*C or C*Q' or C*Q.
*
* LDC (input) INTEGER
* The leading dimension of the array C. LDC >= max(1,M).
*
* WORK (workspace) REAL 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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sormr3
USAGE:
info, c = NumRu::Lapack.sormr3( side, trans, l, a, tau, c, [:usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORMR3( SIDE, TRANS, M, N, K, L, A, LDA, TAU, C, LDC, WORK, INFO )
* Purpose
* =======
*
* SORMR3 overwrites the general real m by n matrix C with
*
* Q * C if SIDE = 'L' and TRANS = 'N', or
*
* Q'* C if SIDE = 'L' and TRANS = 'T', or
*
* C * Q if SIDE = 'R' and TRANS = 'N', or
*
* C * Q' if SIDE = 'R' and TRANS = 'T',
*
* where Q is a real orthogonal matrix defined as the product of k
* elementary reflectors
*
* Q = H(1) H(2) . . . H(k)
*
* as returned by STZRZF. Q is of order m if SIDE = 'L' and of order n
* if SIDE = 'R'.
*
* Arguments
* =========
*
* SIDE (input) CHARACTER*1
* = 'L': apply Q or Q' from the Left
* = 'R': apply Q or Q' from the Right
*
* TRANS (input) CHARACTER*1
* = 'N': apply Q (No transpose)
* = 'T': apply Q' (Transpose)
*
* 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.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines
* the matrix Q.
* If SIDE = 'L', M >= K >= 0;
* if SIDE = 'R', N >= K >= 0.
*
* L (input) INTEGER
* The number of columns of the matrix A containing
* the meaningful part of the Householder reflectors.
* If SIDE = 'L', M >= L >= 0, if SIDE = 'R', N >= L >= 0.
*
* A (input) REAL array, dimension
* (LDA,M) if SIDE = 'L',
* (LDA,N) if SIDE = 'R'
* The i-th row must contain the vector which defines the
* elementary reflector H(i), for i = 1,2,...,k, as returned by
* STZRZF in the last k rows of its array argument A.
* A is modified by the routine but restored on exit.
*
* LDA (input) INTEGER
* The leading dimension of the array A. LDA >= max(1,K).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by STZRZF.
*
* C (input/output) REAL array, dimension (LDC,N)
* On entry, the m-by-n matrix C.
* On exit, C is overwritten by Q*C or Q'*C or C*Q' or C*Q.
*
* LDC (input) INTEGER
* The leading dimension of the array C. LDC >= max(1,M).
*
* WORK (workspace) REAL 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
*
* Further Details
* ===============
*
* Based on contributions by
* A. Petitet, Computer Science Dept., Univ. of Tenn., Knoxville, USA
*
* =====================================================================
*
* .. Local Scalars ..
LOGICAL LEFT, NOTRAN
INTEGER I, I1, I2, I3, IC, JA, JC, MI, NI, NQ
* ..
* .. External Functions ..
LOGICAL LSAME
EXTERNAL LSAME
* ..
* .. External Subroutines ..
EXTERNAL SLARZ, XERBLA
* ..
* .. Intrinsic Functions ..
INTRINSIC MAX
* ..
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sormrq
USAGE:
work, info, c = NumRu::Lapack.sormrq( side, trans, a, tau, c, [:lwork => lwork, :usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORMRQ( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK, LWORK, INFO )
* Purpose
* =======
*
* SORMRQ overwrites the general real M-by-N matrix C with
*
* SIDE = 'L' SIDE = 'R'
* TRANS = 'N': Q * C C * Q
* TRANS = 'T': Q**T * C C * Q**T
*
* where Q is a real orthogonal matrix defined as the product of k
* elementary reflectors
*
* Q = H(1) H(2) . . . H(k)
*
* as returned by SGERQF. Q is of order M if SIDE = 'L' and of order N
* if SIDE = 'R'.
*
* Arguments
* =========
*
* SIDE (input) CHARACTER*1
* = 'L': apply Q or Q**T from the Left;
* = 'R': apply Q or Q**T from the Right.
*
* TRANS (input) CHARACTER*1
* = 'N': No transpose, apply Q;
* = 'T': Transpose, apply Q**T.
*
* 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.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines
* the matrix Q.
* If SIDE = 'L', M >= K >= 0;
* if SIDE = 'R', N >= K >= 0.
*
* A (input) REAL array, dimension
* (LDA,M) if SIDE = 'L',
* (LDA,N) if SIDE = 'R'
* The i-th row must contain the vector which defines the
* elementary reflector H(i), for i = 1,2,...,k, as returned by
* SGERQF in the last k rows of its array argument A.
* A is modified by the routine but restored on exit.
*
* LDA (input) INTEGER
* The leading dimension of the array A. LDA >= max(1,K).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SGERQF.
*
* C (input/output) REAL array, dimension (LDC,N)
* On entry, the M-by-N matrix C.
* On exit, C is overwritten by Q*C or Q**T*C or C*Q**T or C*Q.
*
* LDC (input) INTEGER
* The leading dimension of the array C. LDC >= max(1,M).
*
* WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
* On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
*
* LWORK (input) INTEGER
* The dimension of the array WORK.
* If SIDE = 'L', LWORK >= max(1,N);
* if SIDE = 'R', LWORK >= max(1,M).
* For optimum performance LWORK >= N*NB if SIDE = 'L', and
* LWORK >= M*NB if SIDE = 'R', where NB is the optimal
* blocksize.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the WORK array, and no error
* message related to LWORK is issued by XERBLA.
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument had an illegal value
*
* =====================================================================
*
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sormrz
USAGE:
work, info, c = NumRu::Lapack.sormrz( side, trans, l, a, tau, c, [:lwork => lwork, :usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORMRZ( SIDE, TRANS, M, N, K, L, A, LDA, TAU, C, LDC, WORK, LWORK, INFO )
* Purpose
* =======
*
* SORMRZ overwrites the general real M-by-N matrix C with
*
* SIDE = 'L' SIDE = 'R'
* TRANS = 'N': Q * C C * Q
* TRANS = 'T': Q**T * C C * Q**T
*
* where Q is a real orthogonal matrix defined as the product of k
* elementary reflectors
*
* Q = H(1) H(2) . . . H(k)
*
* as returned by STZRZF. Q is of order M if SIDE = 'L' and of order N
* if SIDE = 'R'.
*
* Arguments
* =========
*
* SIDE (input) CHARACTER*1
* = 'L': apply Q or Q**T from the Left;
* = 'R': apply Q or Q**T from the Right.
*
* TRANS (input) CHARACTER*1
* = 'N': No transpose, apply Q;
* = 'T': Transpose, apply Q**T.
*
* 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.
*
* K (input) INTEGER
* The number of elementary reflectors whose product defines
* the matrix Q.
* If SIDE = 'L', M >= K >= 0;
* if SIDE = 'R', N >= K >= 0.
*
* L (input) INTEGER
* The number of columns of the matrix A containing
* the meaningful part of the Householder reflectors.
* If SIDE = 'L', M >= L >= 0, if SIDE = 'R', N >= L >= 0.
*
* A (input) REAL array, dimension
* (LDA,M) if SIDE = 'L',
* (LDA,N) if SIDE = 'R'
* The i-th row must contain the vector which defines the
* elementary reflector H(i), for i = 1,2,...,k, as returned by
* STZRZF in the last k rows of its array argument A.
* A is modified by the routine but restored on exit.
*
* LDA (input) INTEGER
* The leading dimension of the array A. LDA >= max(1,K).
*
* TAU (input) REAL array, dimension (K)
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by STZRZF.
*
* C (input/output) REAL 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/output) REAL array, dimension (MAX(1,LWORK))
* On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
*
* LWORK (input) INTEGER
* The dimension of the array WORK.
* If SIDE = 'L', LWORK >= max(1,N);
* if SIDE = 'R', LWORK >= max(1,M).
* For optimum performance LWORK >= N*NB if SIDE = 'L', and
* LWORK >= M*NB if SIDE = 'R', where NB is the optimal
* blocksize.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the WORK array, and no error
* message related to LWORK is issued by XERBLA.
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument had an illegal value
*
* Further Details
* ===============
*
* Based on contributions by
* A. Petitet, Computer Science Dept., Univ. of Tenn., Knoxville, USA
*
* =====================================================================
*
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sormtr
USAGE:
work, info, c = NumRu::Lapack.sormtr( side, uplo, trans, a, tau, c, [:lwork => lwork, :usage => usage, :help => help])
FORTRAN MANUAL
SUBROUTINE SORMTR( SIDE, UPLO, TRANS, M, N, A, LDA, TAU, C, LDC, WORK, LWORK, INFO )
* Purpose
* =======
*
* SORMTR overwrites the general real M-by-N matrix C with
*
* SIDE = 'L' SIDE = 'R'
* TRANS = 'N': Q * C C * Q
* TRANS = 'T': Q**T * C C * Q**T
*
* where Q is a real orthogonal 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 SSYTRD:
*
* 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**T from the Left;
* = 'R': apply Q or Q**T from the Right.
*
* UPLO (input) CHARACTER*1
* = 'U': Upper triangle of A contains elementary reflectors
* from SSYTRD;
* = 'L': Lower triangle of A contains elementary reflectors
* from SSYTRD.
*
* TRANS (input) CHARACTER*1
* = 'N': No transpose, apply Q;
* = 'T': Transpose, apply Q**T.
*
* 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.
*
* A (input) REAL array, dimension
* (LDA,M) if SIDE = 'L'
* (LDA,N) if SIDE = 'R'
* The vectors which define the elementary reflectors, as
* returned by SSYTRD.
*
* LDA (input) INTEGER
* The leading dimension of the array A.
* LDA >= max(1,M) if SIDE = 'L'; LDA >= max(1,N) if SIDE = 'R'.
*
* TAU (input) REAL array, dimension
* (M-1) if SIDE = 'L'
* (N-1) if SIDE = 'R'
* TAU(i) must contain the scalar factor of the elementary
* reflector H(i), as returned by SSYTRD.
*
* C (input/output) REAL array, dimension (LDC,N)
* On entry, the M-by-N matrix C.
* On exit, C is overwritten by Q*C or Q**T*C or C*Q**T or C*Q.
*
* LDC (input) INTEGER
* The leading dimension of the array C. LDC >= max(1,M).
*
* WORK (workspace/output) REAL array, dimension (MAX(1,LWORK))
* On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
*
* LWORK (input) INTEGER
* The dimension of the array WORK.
* If SIDE = 'L', LWORK >= max(1,N);
* if SIDE = 'R', LWORK >= max(1,M).
* For optimum performance LWORK >= N*NB if SIDE = 'L', and
* LWORK >= M*NB if SIDE = 'R', where NB is the optimal
* blocksize.
*
* If LWORK = -1, then a workspace query is assumed; the routine
* only calculates the optimal size of the WORK array, returns
* this value as the first entry of the WORK array, and no error
* message related to LWORK is issued by XERBLA.
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument had an illegal value
*
* =====================================================================
*
* .. Local Scalars ..
LOGICAL LEFT, LQUERY, UPPER
INTEGER I1, I2, IINFO, LWKOPT, MI, NI, NB, NQ, NW
* ..
* .. External Functions ..
LOGICAL LSAME
INTEGER ILAENV
EXTERNAL ILAENV, LSAME
* ..
* .. External Subroutines ..
EXTERNAL SORMQL, SORMQR, XERBLA
* ..
* .. Intrinsic Functions ..
INTRINSIC MAX
* ..
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