| @@ -44,7 +44,7 @@ | |||
| *> \verbatim | |||
| *> | |||
| *> ZPORFSX improves the computed solution to a system of linear | |||
| *> equations when the coefficient matrix is symmetric positive | |||
| *> equations when the coefficient matrix is Hermitian positive | |||
| *> definite, and provides error bounds and backward error estimates | |||
| *> for the solution. In addition to normwise error bound, the code | |||
| *> provides maximum componentwise error bound if possible. See | |||
| @@ -103,7 +103,7 @@ | |||
| *> \param[in] A | |||
| *> \verbatim | |||
| *> A is COMPLEX*16 array, dimension (LDA,N) | |||
| *> The symmetric matrix A. If UPLO = 'U', the leading N-by-N | |||
| *> The Hermitian matrix A. If UPLO = 'U', the leading N-by-N | |||
| *> upper triangular part of A contains the upper triangular part | |||
| *> of the matrix A, and the strictly lower triangular part of A | |||
| *> is not referenced. If UPLO = 'L', the leading N-by-N lower | |||
| @@ -134,7 +134,7 @@ | |||
| *> \param[in,out] S | |||
| *> \verbatim | |||
| *> S is DOUBLE PRECISION array, dimension (N) | |||
| *> The row scale factors for A. If EQUED = 'Y', A is multiplied on | |||
| *> The scale factors for A. If EQUED = 'Y', A is multiplied on | |||
| *> the left and right by diag(S). S is an input argument if FACT = | |||
| *> 'F'; otherwise, S is an output argument. If FACT = 'F' and EQUED | |||
| *> = 'Y', each element of S must be positive. If S is output, each | |||
| @@ -262,7 +262,7 @@ | |||
| *> information as described below. There currently are up to three | |||
| *> pieces of information returned for each right-hand side. If | |||
| *> componentwise accuracy is not requested (PARAMS(3) = 0.0), then | |||
| *> ERR_BNDS_COMP is not accessed. If N_ERR_BNDS .LT. 3, then at most | |||
| *> ERR_BNDS_COMP is not accessed. If N_ERR_BNDS < 3, then at most | |||
| *> the first (:,N_ERR_BNDS) entries are returned. | |||
| *> | |||
| *> The first index in ERR_BNDS_COMP(i,:) corresponds to the ith | |||
| @@ -298,14 +298,14 @@ | |||
| *> \param[in] NPARAMS | |||
| *> \verbatim | |||
| *> NPARAMS is INTEGER | |||
| *> Specifies the number of parameters set in PARAMS. If .LE. 0, the | |||
| *> Specifies the number of parameters set in PARAMS. If <= 0, the | |||
| *> PARAMS array is never referenced and default values are used. | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in,out] PARAMS | |||
| *> \verbatim | |||
| *> PARAMS is DOUBLE PRECISION array, dimension NPARAMS | |||
| *> Specifies algorithm parameters. If an entry is .LT. 0.0, then | |||
| *> Specifies algorithm parameters. If an entry is < 0.0, then | |||
| *> that entry will be filled with default value used for that | |||
| *> parameter. Only positions up to NPARAMS are accessed; defaults | |||
| *> are used for higher-numbered parameters. | |||
| @@ -313,9 +313,9 @@ | |||
| *> PARAMS(LA_LINRX_ITREF_I = 1) : Whether to perform iterative | |||
| *> refinement or not. | |||
| *> Default: 1.0D+0 | |||
| *> = 0.0 : No refinement is performed, and no error bounds are | |||
| *> = 0.0: No refinement is performed, and no error bounds are | |||
| *> computed. | |||
| *> = 1.0 : Use the double-precision refinement algorithm, | |||
| *> = 1.0: Use the double-precision refinement algorithm, | |||
| *> possibly with doubled-single computations if the | |||
| *> compilation environment does not support DOUBLE | |||
| *> PRECISION. | |||
| @@ -45,7 +45,7 @@ | |||
| *> | |||
| *> ZPOSVXX uses the Cholesky factorization A = U**T*U or A = L*L**T | |||
| *> to compute the solution to a complex*16 system of linear equations | |||
| *> A * X = B, where A is an N-by-N symmetric positive definite matrix | |||
| *> A * X = B, where A is an N-by-N Hermitian positive definite matrix | |||
| *> and X and B are N-by-NRHS matrices. | |||
| *> | |||
| *> If requested, both normwise and maximum componentwise error bounds | |||
| @@ -157,7 +157,7 @@ | |||
| *> \param[in,out] A | |||
| *> \verbatim | |||
| *> A is COMPLEX*16 array, dimension (LDA,N) | |||
| *> On entry, the symmetric matrix A, except if FACT = 'F' and EQUED = | |||
| *> On entry, the Hermitian matrix A, except if FACT = 'F' and EQUED = | |||
| *> 'Y', then A must contain the equilibrated matrix | |||
| *> diag(S)*A*diag(S). If UPLO = 'U', the leading N-by-N upper | |||
| *> triangular part of A contains the upper triangular part of the | |||
| @@ -365,7 +365,7 @@ | |||
| *> information as described below. There currently are up to three | |||
| *> pieces of information returned for each right-hand side. If | |||
| *> componentwise accuracy is not requested (PARAMS(3) = 0.0), then | |||
| *> ERR_BNDS_COMP is not accessed. If N_ERR_BNDS .LT. 3, then at most | |||
| *> ERR_BNDS_COMP is not accessed. If N_ERR_BNDS < 3, then at most | |||
| *> the first (:,N_ERR_BNDS) entries are returned. | |||
| *> | |||
| *> The first index in ERR_BNDS_COMP(i,:) corresponds to the ith | |||
| @@ -401,14 +401,14 @@ | |||
| *> \param[in] NPARAMS | |||
| *> \verbatim | |||
| *> NPARAMS is INTEGER | |||
| *> Specifies the number of parameters set in PARAMS. If .LE. 0, the | |||
| *> Specifies the number of parameters set in PARAMS. If <= 0, the | |||
| *> PARAMS array is never referenced and default values are used. | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in,out] PARAMS | |||
| *> \verbatim | |||
| *> PARAMS is DOUBLE PRECISION array, dimension NPARAMS | |||
| *> Specifies algorithm parameters. If an entry is .LT. 0.0, then | |||
| *> Specifies algorithm parameters. If an entry is < 0.0, then | |||
| *> that entry will be filled with default value used for that | |||
| *> parameter. Only positions up to NPARAMS are accessed; defaults | |||
| *> are used for higher-numbered parameters. | |||
| @@ -416,9 +416,9 @@ | |||
| *> PARAMS(LA_LINRX_ITREF_I = 1) : Whether to perform iterative | |||
| *> refinement or not. | |||
| *> Default: 1.0D+0 | |||
| *> = 0.0 : No refinement is performed, and no error bounds are | |||
| *> = 0.0: No refinement is performed, and no error bounds are | |||
| *> computed. | |||
| *> = 1.0 : Use the extra-precise refinement algorithm. | |||
| *> = 1.0: Use the extra-precise refinement algorithm. | |||
| *> (other values are reserved for future use) | |||
| *> | |||
| *> PARAMS(LA_LINRX_ITHRESH_I = 2) : Maximum number of residual | |||
| @@ -24,7 +24,7 @@ | |||
| *> | |||
| *> \verbatim | |||
| *> | |||
| *> ZPOTRF2 computes the Cholesky factorization of a real symmetric | |||
| *> ZPOTRF2 computes the Cholesky factorization of a Hermitian | |||
| *> positive definite matrix A using the recursive algorithm. | |||
| *> | |||
| *> The factorization has the form | |||
| @@ -63,7 +63,7 @@ | |||
| *> \param[in,out] A | |||
| *> \verbatim | |||
| *> A is COMPLEX*16 array, dimension (LDA,N) | |||
| *> On entry, the symmetric matrix A. If UPLO = 'U', the leading | |||
| *> On entry, the Hermitian matrix A. If UPLO = 'U', the leading | |||
| *> N-by-N upper triangular part of A contains the upper | |||
| *> triangular part of the matrix A, and the strictly lower | |||
| *> triangular part of A is not referenced. If UPLO = 'L', the | |||
| @@ -250,13 +250,13 @@ | |||
| *> \param[in,out] TRYRAC | |||
| *> \verbatim | |||
| *> TRYRAC is LOGICAL | |||
| *> If TRYRAC.EQ..TRUE., indicates that the code should check whether | |||
| *> If TRYRAC = .TRUE., indicates that the code should check whether | |||
| *> the tridiagonal matrix defines its eigenvalues to high relative | |||
| *> accuracy. If so, the code uses relative-accuracy preserving | |||
| *> algorithms that might be (a bit) slower depending on the matrix. | |||
| *> If the matrix does not define its eigenvalues to high relative | |||
| *> accuracy, the code can uses possibly faster algorithms. | |||
| *> If TRYRAC.EQ..FALSE., the code is not required to guarantee | |||
| *> If TRYRAC = .FALSE., the code is not required to guarantee | |||
| *> relatively accurate eigenvalues and can use the fastest possible | |||
| *> techniques. | |||
| *> On exit, a .TRUE. TRYRAC will be set to .FALSE. if the matrix | |||
| @@ -19,7 +19,7 @@ | |||
| * =========== | |||
| * | |||
| * SUBROUTINE ZSYCON_3( UPLO, N, A, LDA, E, IPIV, ANORM, RCOND, | |||
| * WORK, IWORK, INFO ) | |||
| * WORK, INFO ) | |||
| * | |||
| * .. Scalar Arguments .. | |||
| * CHARACTER UPLO | |||
| @@ -27,7 +27,7 @@ | |||
| * DOUBLE PRECISION ANORM, RCOND | |||
| * .. | |||
| * .. Array Arguments .. | |||
| * INTEGER IPIV( * ), IWORK( * ) | |||
| * INTEGER IPIV( * ) | |||
| * COMPLEX*16 A( LDA, * ), E ( * ), WORK( * ) | |||
| * .. | |||
| * | |||
| @@ -129,11 +129,6 @@ | |||
| *> WORK is COMPLEX*16 array, dimension (2*N) | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[out] IWORK | |||
| *> \verbatim | |||
| *> IWORK is INTEGER array, dimension (N) | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[out] INFO | |||
| *> \verbatim | |||
| *> INFO is INTEGER | |||
| @@ -294,7 +294,7 @@ | |||
| * | |||
| * Convert PERMUTATIONS and IPIV | |||
| * | |||
| * Apply permutaions to submatrices of upper part of A | |||
| * Apply permutations to submatrices of upper part of A | |||
| * in factorization order where i decreases from N to 1 | |||
| * | |||
| I = N | |||
| @@ -347,7 +347,7 @@ | |||
| * | |||
| * Revert PERMUTATIONS and IPIV | |||
| * | |||
| * Apply permutaions to submatrices of upper part of A | |||
| * Apply permutations to submatrices of upper part of A | |||
| * in reverse factorization order where i increases from 1 to N | |||
| * | |||
| I = 1 | |||
| @@ -438,7 +438,7 @@ | |||
| * | |||
| * Convert PERMUTATIONS and IPIV | |||
| * | |||
| * Apply permutaions to submatrices of lower part of A | |||
| * Apply permutations to submatrices of lower part of A | |||
| * in factorization order where k increases from 1 to N | |||
| * | |||
| I = 1 | |||
| @@ -491,7 +491,7 @@ | |||
| * | |||
| * Revert PERMUTATIONS and IPIV | |||
| * | |||
| * Apply permutaions to submatrices of lower part of A | |||
| * Apply permutations to submatrices of lower part of A | |||
| * in reverse factorization order where i decreases from N to 1 | |||
| * | |||
| I = N | |||
| @@ -285,7 +285,7 @@ | |||
| * | |||
| * Convert PERMUTATIONS | |||
| * | |||
| * Apply permutaions to submatrices of upper part of A | |||
| * Apply permutations to submatrices of upper part of A | |||
| * in factorization order where i decreases from N to 1 | |||
| * | |||
| I = N | |||
| @@ -336,7 +336,7 @@ | |||
| * | |||
| * Revert PERMUTATIONS | |||
| * | |||
| * Apply permutaions to submatrices of upper part of A | |||
| * Apply permutations to submatrices of upper part of A | |||
| * in reverse factorization order where i increases from 1 to N | |||
| * | |||
| I = 1 | |||
| @@ -426,7 +426,7 @@ | |||
| * | |||
| * Convert PERMUTATIONS | |||
| * | |||
| * Apply permutaions to submatrices of lower part of A | |||
| * Apply permutations to submatrices of lower part of A | |||
| * in factorization order where i increases from 1 to N | |||
| * | |||
| I = 1 | |||
| @@ -477,7 +477,7 @@ | |||
| * | |||
| * Revert PERMUTATIONS | |||
| * | |||
| * Apply permutaions to submatrices of lower part of A | |||
| * Apply permutations to submatrices of lower part of A | |||
| * in reverse factorization order where i decreases from N to 1 | |||
| * | |||
| I = N | |||
| @@ -271,7 +271,7 @@ | |||
| *> information as described below. There currently are up to three | |||
| *> pieces of information returned for each right-hand side. If | |||
| *> componentwise accuracy is not requested (PARAMS(3) = 0.0), then | |||
| *> ERR_BNDS_COMP is not accessed. If N_ERR_BNDS .LT. 3, then at most | |||
| *> ERR_BNDS_COMP is not accessed. If N_ERR_BNDS < 3, then at most | |||
| *> the first (:,N_ERR_BNDS) entries are returned. | |||
| *> | |||
| *> The first index in ERR_BNDS_COMP(i,:) corresponds to the ith | |||
| @@ -307,14 +307,14 @@ | |||
| *> \param[in] NPARAMS | |||
| *> \verbatim | |||
| *> NPARAMS is INTEGER | |||
| *> Specifies the number of parameters set in PARAMS. If .LE. 0, the | |||
| *> Specifies the number of parameters set in PARAMS. If <= 0, the | |||
| *> PARAMS array is never referenced and default values are used. | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in,out] PARAMS | |||
| *> \verbatim | |||
| *> PARAMS is DOUBLE PRECISION array, dimension NPARAMS | |||
| *> Specifies algorithm parameters. If an entry is .LT. 0.0, then | |||
| *> Specifies algorithm parameters. If an entry is < 0.0, then | |||
| *> that entry will be filled with default value used for that | |||
| *> parameter. Only positions up to NPARAMS are accessed; defaults | |||
| *> are used for higher-numbered parameters. | |||
| @@ -322,9 +322,9 @@ | |||
| *> PARAMS(LA_LINRX_ITREF_I = 1) : Whether to perform iterative | |||
| *> refinement or not. | |||
| *> Default: 1.0D+0 | |||
| *> = 0.0 : No refinement is performed, and no error bounds are | |||
| *> = 0.0: No refinement is performed, and no error bounds are | |||
| *> computed. | |||
| *> = 1.0 : Use the double-precision refinement algorithm, | |||
| *> = 1.0: Use the double-precision refinement algorithm, | |||
| *> possibly with doubled-single computations if the | |||
| *> compilation environment does not support DOUBLE | |||
| *> PRECISION. | |||
| @@ -42,7 +42,7 @@ | |||
| *> matrices. | |||
| *> | |||
| *> Aasen's algorithm is used to factor A as | |||
| *> A = U * T * U**T, if UPLO = 'U', or | |||
| *> A = U**T * T * U, if UPLO = 'U', or | |||
| *> A = L * T * L**T, if UPLO = 'L', | |||
| *> where U (or L) is a product of permutation and unit upper (lower) | |||
| *> triangular matrices, and T is symmetric tridiagonal. The factored | |||
| @@ -86,7 +86,7 @@ | |||
| *> | |||
| *> On exit, if INFO = 0, the tridiagonal matrix T and the | |||
| *> multipliers used to obtain the factor U or L from the | |||
| *> factorization A = U*T*U**T or A = L*T*L**T as computed by | |||
| *> factorization A = U**T*T*U or A = L*T*L**T as computed by | |||
| *> ZSYTRF. | |||
| *> \endverbatim | |||
| *> | |||
| @@ -230,7 +230,7 @@ | |||
| RETURN | |||
| END IF | |||
| * | |||
| * Compute the factorization A = U*T*U**T or A = L*T*L**T. | |||
| * Compute the factorization A = U**T*T*U or A = L*T*L**T. | |||
| * | |||
| CALL ZSYTRF_AA( UPLO, N, A, LDA, IPIV, WORK, LWORK, INFO ) | |||
| IF( INFO.EQ.0 ) THEN | |||
| @@ -43,8 +43,8 @@ | |||
| *> matrices. | |||
| *> | |||
| *> Aasen's 2-stage algorithm is used to factor A as | |||
| *> A = U * T * U**H, if UPLO = 'U', or | |||
| *> A = L * T * L**H, if UPLO = 'L', | |||
| *> A = U**T * T * U, if UPLO = 'U', or | |||
| *> A = L * T * L**T, if UPLO = 'L', | |||
| *> where U (or L) is a product of permutation and unit upper (lower) | |||
| *> triangular matrices, and T is symmetric and band. The matrix T is | |||
| *> then LU-factored with partial pivoting. The factored form of A | |||
| @@ -257,7 +257,7 @@ | |||
| END IF | |||
| * | |||
| * | |||
| * Compute the factorization A = U*T*U**H or A = L*T*L**H. | |||
| * Compute the factorization A = U**T*T*U or A = L*T*L**T. | |||
| * | |||
| CALL ZSYTRF_AA_2STAGE( UPLO, N, A, LDA, TB, LTB, IPIV, IPIV2, | |||
| $ WORK, LWORK, INFO ) | |||
| @@ -378,7 +378,7 @@ | |||
| *> information as described below. There currently are up to three | |||
| *> pieces of information returned for each right-hand side. If | |||
| *> componentwise accuracy is not requested (PARAMS(3) = 0.0), then | |||
| *> ERR_BNDS_COMP is not accessed. If N_ERR_BNDS .LT. 3, then at most | |||
| *> ERR_BNDS_COMP is not accessed. If N_ERR_BNDS < 3, then at most | |||
| *> the first (:,N_ERR_BNDS) entries are returned. | |||
| *> | |||
| *> The first index in ERR_BNDS_COMP(i,:) corresponds to the ith | |||
| @@ -414,14 +414,14 @@ | |||
| *> \param[in] NPARAMS | |||
| *> \verbatim | |||
| *> NPARAMS is INTEGER | |||
| *> Specifies the number of parameters set in PARAMS. If .LE. 0, the | |||
| *> Specifies the number of parameters set in PARAMS. If <= 0, the | |||
| *> PARAMS array is never referenced and default values are used. | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in,out] PARAMS | |||
| *> \verbatim | |||
| *> PARAMS is DOUBLE PRECISION array, dimension NPARAMS | |||
| *> Specifies algorithm parameters. If an entry is .LT. 0.0, then | |||
| *> Specifies algorithm parameters. If an entry is < 0.0, then | |||
| *> that entry will be filled with default value used for that | |||
| *> parameter. Only positions up to NPARAMS are accessed; defaults | |||
| *> are used for higher-numbered parameters. | |||
| @@ -429,9 +429,9 @@ | |||
| *> PARAMS(LA_LINRX_ITREF_I = 1) : Whether to perform iterative | |||
| *> refinement or not. | |||
| *> Default: 1.0D+0 | |||
| *> = 0.0 : No refinement is performed, and no error bounds are | |||
| *> = 0.0: No refinement is performed, and no error bounds are | |||
| *> computed. | |||
| *> = 1.0 : Use the extra-precise refinement algorithm. | |||
| *> = 1.0: Use the extra-precise refinement algorithm. | |||
| *> (other values are reserved for future use) | |||
| *> | |||
| *> PARAMS(LA_LINRX_ITHRESH_I = 2) : Maximum number of residual | |||
| @@ -321,7 +321,7 @@ | |||
| * | |||
| * Factorize A as U*D*U**T using the upper triangle of A | |||
| * | |||
| * Initilize the first entry of array E, where superdiagonal | |||
| * Initialize the first entry of array E, where superdiagonal | |||
| * elements of D are stored | |||
| * | |||
| E( 1 ) = CZERO | |||
| @@ -632,7 +632,7 @@ | |||
| * | |||
| * Factorize A as L*D*L**T using the lower triangle of A | |||
| * | |||
| * Initilize the unused last entry of the subdiagonal array E. | |||
| * Initialize the unused last entry of the subdiagonal array E. | |||
| * | |||
| E( N ) = CZERO | |||
| * | |||
| @@ -43,7 +43,7 @@ | |||
| *> | |||
| *> where U (or L) is a product of permutation and unit upper (lower) | |||
| *> triangular matrices, and D is symmetric and block diagonal with | |||
| *> with 1-by-1 and 2-by-2 diagonal blocks. | |||
| *> 1-by-1 and 2-by-2 diagonal blocks. | |||
| *> | |||
| *> This is the blocked version of the algorithm, calling Level 3 BLAS. | |||
| *> \endverbatim | |||
| @@ -37,7 +37,7 @@ | |||
| *> ZSYTRF_AA computes the factorization of a complex symmetric matrix A | |||
| *> using the Aasen's algorithm. The form of the factorization is | |||
| *> | |||
| *> A = U*T*U**T or A = L*T*L**T | |||
| *> A = U**T*T*U or A = L*T*L**T | |||
| *> | |||
| *> where U (or L) is a product of permutation and unit upper (lower) | |||
| *> triangular matrices, and T is a complex symmetric tridiagonal matrix. | |||
| @@ -223,7 +223,7 @@ | |||
| IF( UPPER ) THEN | |||
| * | |||
| * ..................................................... | |||
| * Factorize A as L*D*L**T using the upper triangle of A | |||
| * Factorize A as U**T*D*U using the upper triangle of A | |||
| * ..................................................... | |||
| * | |||
| * Copy first row A(1, 1:N) into H(1:n) (stored in WORK(1:N)) | |||
| @@ -256,7 +256,7 @@ | |||
| $ A( MAX(1, J), J+1 ), LDA, | |||
| $ IPIV( J+1 ), WORK, N, WORK( N*NB+1 ) ) | |||
| * | |||
| * Ajust IPIV and apply it back (J-th step picks (J+1)-th pivot) | |||
| * Adjust IPIV and apply it back (J-th step picks (J+1)-th pivot) | |||
| * | |||
| DO J2 = J+2, MIN(N, J+JB+1) | |||
| IPIV( J2 ) = IPIV( J2 ) + J | |||
| @@ -375,7 +375,7 @@ | |||
| $ A( J+1, MAX(1, J) ), LDA, | |||
| $ IPIV( J+1 ), WORK, N, WORK( N*NB+1 ) ) | |||
| * | |||
| * Ajust IPIV and apply it back (J-th step picks (J+1)-th pivot) | |||
| * Adjust IPIV and apply it back (J-th step picks (J+1)-th pivot) | |||
| * | |||
| DO J2 = J+2, MIN(N, J+JB+1) | |||
| IPIV( J2 ) = IPIV( J2 ) + J | |||
| @@ -38,7 +38,7 @@ | |||
| *> ZSYTRF_AA_2STAGE computes the factorization of a complex symmetric matrix A | |||
| *> using the Aasen's algorithm. The form of the factorization is | |||
| *> | |||
| *> A = U*T*U**T or A = L*T*L**T | |||
| *> A = U**T*T*U or A = L*T*L**T | |||
| *> | |||
| *> where U (or L) is a product of permutation and unit upper (lower) | |||
| *> triangular matrices, and T is a complex symmetric band matrix with the | |||
| @@ -275,7 +275,7 @@ | |||
| IF( UPPER ) THEN | |||
| * | |||
| * ..................................................... | |||
| * Factorize A as L*D*L**T using the upper triangle of A | |||
| * Factorize A as U**T*D*U using the upper triangle of A | |||
| * ..................................................... | |||
| * | |||
| DO J = 0, NT-1 | |||
| @@ -448,12 +448,14 @@ c END IF | |||
| * > Apply pivots to previous columns of L | |||
| CALL ZSWAP( K-1, A( (J+1)*NB+1, I1 ), 1, | |||
| $ A( (J+1)*NB+1, I2 ), 1 ) | |||
| * > Swap A(I1+1:M, I1) with A(I2, I1+1:M) | |||
| CALL ZSWAP( I2-I1-1, A( I1, I1+1 ), LDA, | |||
| $ A( I1+1, I2 ), 1 ) | |||
| * > Swap A(I1+1:M, I1) with A(I2, I1+1:M) | |||
| IF( I2.GT.(I1+1) ) | |||
| $ CALL ZSWAP( I2-I1-1, A( I1, I1+1 ), LDA, | |||
| $ A( I1+1, I2 ), 1 ) | |||
| * > Swap A(I2+1:M, I1) with A(I2+1:M, I2) | |||
| CALL ZSWAP( N-I2, A( I1, I2+1 ), LDA, | |||
| $ A( I2, I2+1 ), LDA ) | |||
| IF( I2.LT.N ) | |||
| $ CALL ZSWAP( N-I2, A( I1, I2+1 ), LDA, | |||
| $ A( I2, I2+1 ), LDA ) | |||
| * > Swap A(I1, I1) with A(I2, I2) | |||
| PIV = A( I1, I1 ) | |||
| A( I1, I1 ) = A( I2, I2 ) | |||
| @@ -637,11 +639,13 @@ c END IF | |||
| CALL ZSWAP( K-1, A( I1, (J+1)*NB+1 ), LDA, | |||
| $ A( I2, (J+1)*NB+1 ), LDA ) | |||
| * > Swap A(I1+1:M, I1) with A(I2, I1+1:M) | |||
| CALL ZSWAP( I2-I1-1, A( I1+1, I1 ), 1, | |||
| $ A( I2, I1+1 ), LDA ) | |||
| IF( I2.GT.(I1+1) ) | |||
| $ CALL ZSWAP( I2-I1-1, A( I1+1, I1 ), 1, | |||
| $ A( I2, I1+1 ), LDA ) | |||
| * > Swap A(I2+1:M, I1) with A(I2+1:M, I2) | |||
| CALL ZSWAP( N-I2, A( I2+1, I1 ), 1, | |||
| $ A( I2+1, I2 ), 1 ) | |||
| IF( I2.LT.N ) | |||
| $ CALL ZSWAP( N-I2, A( I2+1, I1 ), 1, | |||
| $ A( I2+1, I2 ), 1 ) | |||
| * > Swap A(I1, I1) with A(I2, I2) | |||
| PIV = A( I1, I1 ) | |||
| A( I1, I1 ) = A( I2, I2 ) | |||
| @@ -62,7 +62,7 @@ | |||
| *> \param[in,out] A | |||
| *> \verbatim | |||
| *> A is COMPLEX*16 array, dimension (LDA,N) | |||
| *> On entry, the NB diagonal matrix D and the multipliers | |||
| *> On entry, the block diagonal matrix D and the multipliers | |||
| *> used to obtain the factor U or L as computed by ZSYTRF. | |||
| *> | |||
| *> On exit, if INFO = 0, the (symmetric) inverse of the original | |||
| @@ -82,7 +82,7 @@ | |||
| *> \param[in] IPIV | |||
| *> \verbatim | |||
| *> IPIV is INTEGER array, dimension (N) | |||
| *> Details of the interchanges and the NB structure of D | |||
| *> Details of the interchanges and the block structure of D | |||
| *> as determined by ZSYTRF. | |||
| *> \endverbatim | |||
| *> | |||
| @@ -36,7 +36,7 @@ | |||
| *> | |||
| *> \verbatim | |||
| *> | |||
| *> ZSYTRS2 solves a system of linear equations A*X = B with a real | |||
| *> ZSYTRS2 solves a system of linear equations A*X = B with a complex | |||
| *> symmetric matrix A using the factorization A = U*D*U**T or | |||
| *> A = L*D*L**T computed by ZSYTRF and converted by ZSYCONV. | |||
| *> \endverbatim | |||
| @@ -37,7 +37,7 @@ | |||
| *> \verbatim | |||
| *> | |||
| *> ZSYTRS_AA solves a system of linear equations A*X = B with a complex | |||
| *> symmetric matrix A using the factorization A = U*T*U**T or | |||
| *> symmetric matrix A using the factorization A = U**T*T*U or | |||
| *> A = L*T*L**T computed by ZSYTRF_AA. | |||
| *> \endverbatim | |||
| * | |||
| @@ -49,7 +49,7 @@ | |||
| *> UPLO is CHARACTER*1 | |||
| *> Specifies whether the details of the factorization are stored | |||
| *> as an upper or lower triangular matrix. | |||
| *> = 'U': Upper triangular, form is A = U*T*U**T; | |||
| *> = 'U': Upper triangular, form is A = U**T*T*U; | |||
| *> = 'L': Lower triangular, form is A = L*T*L**T. | |||
| *> \endverbatim | |||
| *> | |||
| @@ -97,14 +97,16 @@ | |||
| *> The leading dimension of the array B. LDB >= max(1,N). | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in] WORK | |||
| *> \param[out] WORK | |||
| *> \verbatim | |||
| *> WORK is DOUBLE array, dimension (MAX(1,LWORK)) | |||
| *> WORK is COMPLEX*16 array, dimension (MAX(1,LWORK)) | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in] LWORK | |||
| *> \verbatim | |||
| *> LWORK is INTEGER, LWORK >= MAX(1,3*N-2). | |||
| *> LWORK is INTEGER | |||
| *> The dimension of the array WORK. LWORK >= max(1,3*N-2). | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[out] INFO | |||
| *> \verbatim | |||
| @@ -198,22 +200,29 @@ | |||
| * | |||
| IF( UPPER ) THEN | |||
| * | |||
| * Solve A*X = B, where A = U*T*U**T. | |||
| * Solve A*X = B, where A = U**T*T*U. | |||
| * | |||
| * 1) Forward substitution with U**T | |||
| * | |||
| IF( N.GT.1 ) THEN | |||
| * | |||
| * Pivot, P**T * B -> B | |||
| * | |||
| * Pivot, P**T * B | |||
| DO K = 1, N | |||
| KP = IPIV( K ) | |||
| IF( KP.NE.K ) | |||
| $ CALL ZSWAP( NRHS, B( K, 1 ), LDB, B( KP, 1 ), LDB ) | |||
| END DO | |||
| * | |||
| DO K = 1, N | |||
| KP = IPIV( K ) | |||
| IF( KP.NE.K ) | |||
| $ CALL ZSWAP( NRHS, B( K, 1 ), LDB, B( KP, 1 ), LDB ) | |||
| END DO | |||
| * Compute U**T \ B -> B [ (U**T \P**T * B) ] | |||
| * | |||
| * Compute (U \P**T * B) -> B [ (U \P**T * B) ] | |||
| CALL ZTRSM( 'L', 'U', 'T', 'U', N-1, NRHS, ONE, A( 1, 2 ), | |||
| $ LDA, B( 2, 1 ), LDB) | |||
| END IF | |||
| * | |||
| CALL ZTRSM('L', 'U', 'T', 'U', N-1, NRHS, ONE, A( 1, 2 ), LDA, | |||
| $ B( 2, 1 ), LDB) | |||
| * 2) Solve with triangular matrix T | |||
| * | |||
| * Compute T \ B -> B [ T \ (U \P**T * B) ] | |||
| * Compute T \ B -> B [ T \ (U**T \P**T * B) ] | |||
| * | |||
| CALL ZLACPY( 'F', 1, N, A( 1, 1 ), LDA+1, WORK( N ), 1) | |||
| IF( N.GT.1 ) THEN | |||
| @@ -223,35 +232,47 @@ | |||
| CALL ZGTSV( N, NRHS, WORK( 1 ), WORK( N ), WORK( 2*N ), B, LDB, | |||
| $ INFO ) | |||
| * | |||
| * Compute (U**T \ B) -> B [ U**T \ (T \ (U \P**T * B) ) ] | |||
| * 3) Backward substitution with U | |||
| * | |||
| CALL ZTRSM( 'L', 'U', 'N', 'U', N-1, NRHS, ONE, A( 1, 2 ), LDA, | |||
| $ B( 2, 1 ), LDB) | |||
| IF( N.GT.1 ) THEN | |||
| * | |||
| * Pivot, P * B [ P * (U**T \ (T \ (U \P**T * B) )) ] | |||
| * Compute U \ B -> B [ U \ (T \ (U**T \P**T * B) ) ] | |||
| * | |||
| DO K = N, 1, -1 | |||
| KP = IPIV( K ) | |||
| IF( KP.NE.K ) | |||
| $ CALL ZSWAP( NRHS, B( K, 1 ), LDB, B( KP, 1 ), LDB ) | |||
| END DO | |||
| CALL ZTRSM( 'L', 'U', 'N', 'U', N-1, NRHS, ONE, A( 1, 2 ), | |||
| $ LDA, B( 2, 1 ), LDB) | |||
| * | |||
| * Pivot, P * B -> B [ P * (U \ (T \ (U**T \P**T * B) )) ] | |||
| * | |||
| DO K = N, 1, -1 | |||
| KP = IPIV( K ) | |||
| IF( KP.NE.K ) | |||
| $ CALL ZSWAP( NRHS, B( K, 1 ), LDB, B( KP, 1 ), LDB ) | |||
| END DO | |||
| END IF | |||
| * | |||
| ELSE | |||
| * | |||
| * Solve A*X = B, where A = L*T*L**T. | |||
| * | |||
| * Pivot, P**T * B | |||
| * 1) Forward substitution with L | |||
| * | |||
| DO K = 1, N | |||
| KP = IPIV( K ) | |||
| IF( KP.NE.K ) | |||
| $ CALL ZSWAP( NRHS, B( K, 1 ), LDB, B( KP, 1 ), LDB ) | |||
| END DO | |||
| IF( N.GT.1 ) THEN | |||
| * | |||
| * Pivot, P**T * B -> B | |||
| * | |||
| * Compute (L \P**T * B) -> B [ (L \P**T * B) ] | |||
| DO K = 1, N | |||
| KP = IPIV( K ) | |||
| IF( KP.NE.K ) | |||
| $ CALL ZSWAP( NRHS, B( K, 1 ), LDB, B( KP, 1 ), LDB ) | |||
| END DO | |||
| * | |||
| * Compute L \ B -> B [ (L \P**T * B) ] | |||
| * | |||
| CALL ZTRSM( 'L', 'L', 'N', 'U', N-1, NRHS, ONE, A( 2, 1 ), | |||
| $ LDA, B( 2, 1 ), LDB) | |||
| END IF | |||
| * | |||
| CALL ZTRSM( 'L', 'L', 'N', 'U', N-1, NRHS, ONE, A( 2, 1 ), LDA, | |||
| $ B( 2, 1 ), LDB) | |||
| * 2) Solve with triangular matrix T | |||
| * | |||
| * Compute T \ B -> B [ T \ (L \P**T * B) ] | |||
| * | |||
| @@ -263,18 +284,23 @@ | |||
| CALL ZGTSV( N, NRHS, WORK( 1 ), WORK(N), WORK( 2*N ), B, LDB, | |||
| $ INFO) | |||
| * | |||
| * Compute (L**T \ B) -> B [ L**T \ (T \ (L \P**T * B) ) ] | |||
| * 3) Backward substitution with L**T | |||
| * | |||
| CALL ZTRSM( 'L', 'L', 'T', 'U', N-1, NRHS, ONE, A( 2, 1 ), LDA, | |||
| $ B( 2, 1 ), LDB) | |||
| IF( N.GT.1 ) THEN | |||
| * | |||
| * Pivot, P * B [ P * (L**T \ (T \ (L \P**T * B) )) ] | |||
| * Compute (L**T \ B) -> B [ L**T \ (T \ (L \P**T * B) ) ] | |||
| * | |||
| DO K = N, 1, -1 | |||
| KP = IPIV( K ) | |||
| IF( KP.NE.K ) | |||
| $ CALL ZSWAP( NRHS, B( K, 1 ), LDB, B( KP, 1 ), LDB ) | |||
| END DO | |||
| CALL ZTRSM( 'L', 'L', 'T', 'U', N-1, NRHS, ONE, A( 2, 1 ), | |||
| $ LDA, B( 2, 1 ), LDB) | |||
| * | |||
| * Pivot, P * B -> B [ P * (L**T \ (T \ (L \P**T * B) )) ] | |||
| * | |||
| DO K = N, 1, -1 | |||
| KP = IPIV( K ) | |||
| IF( KP.NE.K ) | |||
| $ CALL ZSWAP( NRHS, B( K, 1 ), LDB, B( KP, 1 ), LDB ) | |||
| END DO | |||
| END IF | |||
| * | |||
| END IF | |||
| * | |||
| @@ -36,7 +36,7 @@ | |||
| *> \verbatim | |||
| *> | |||
| *> ZSYTRS_AA_2STAGE solves a system of linear equations A*X = B with a complex | |||
| *> symmetric matrix A using the factorization A = U*T*U**T or | |||
| *> symmetric matrix A using the factorization A = U**T*T*U or | |||
| *> A = L*T*L**T computed by ZSYTRF_AA_2STAGE. | |||
| *> \endverbatim | |||
| * | |||
| @@ -48,7 +48,7 @@ | |||
| *> UPLO is CHARACTER*1 | |||
| *> Specifies whether the details of the factorization are stored | |||
| *> as an upper or lower triangular matrix. | |||
| *> = 'U': Upper triangular, form is A = U*T*U**T; | |||
| *> = 'U': Upper triangular, form is A = U**T*T*U; | |||
| *> = 'L': Lower triangular, form is A = L*T*L**T. | |||
| *> \endverbatim | |||
| *> | |||
| @@ -208,15 +208,15 @@ | |||
| * | |||
| IF( UPPER ) THEN | |||
| * | |||
| * Solve A*X = B, where A = U*T*U**T. | |||
| * Solve A*X = B, where A = U**T*T*U. | |||
| * | |||
| IF( N.GT.NB ) THEN | |||
| * | |||
| * Pivot, P**T * B | |||
| * Pivot, P**T * B -> B | |||
| * | |||
| CALL ZLASWP( NRHS, B, LDB, NB+1, N, IPIV, 1 ) | |||
| * | |||
| * Compute (U**T \P**T * B) -> B [ (U**T \P**T * B) ] | |||
| * Compute (U**T \ B) -> B [ (U**T \P**T * B) ] | |||
| * | |||
| CALL ZTRSM( 'L', 'U', 'T', 'U', N-NB, NRHS, ONE, A(1, NB+1), | |||
| $ LDA, B(NB+1, 1), LDB) | |||
| @@ -234,7 +234,7 @@ | |||
| CALL ZTRSM( 'L', 'U', 'N', 'U', N-NB, NRHS, ONE, A(1, NB+1), | |||
| $ LDA, B(NB+1, 1), LDB) | |||
| * | |||
| * Pivot, P * B [ P * (U \ (T \ (U**T \P**T * B) )) ] | |||
| * Pivot, P * B -> B [ P * (U \ (T \ (U**T \P**T * B) )) ] | |||
| * | |||
| CALL ZLASWP( NRHS, B, LDB, NB+1, N, IPIV, -1 ) | |||
| * | |||
| @@ -246,11 +246,11 @@ | |||
| * | |||
| IF( N.GT.NB ) THEN | |||
| * | |||
| * Pivot, P**T * B | |||
| * Pivot, P**T * B -> B | |||
| * | |||
| CALL ZLASWP( NRHS, B, LDB, NB+1, N, IPIV, 1 ) | |||
| * | |||
| * Compute (L \P**T * B) -> B [ (L \P**T * B) ] | |||
| * Compute (L \ B) -> B [ (L \P**T * B) ] | |||
| * | |||
| CALL ZTRSM( 'L', 'L', 'N', 'U', N-NB, NRHS, ONE, A(NB+1, 1), | |||
| $ LDA, B(NB+1, 1), LDB) | |||
| @@ -268,7 +268,7 @@ | |||
| CALL ZTRSM( 'L', 'L', 'T', 'U', N-NB, NRHS, ONE, A(NB+1, 1), | |||
| $ LDA, B(NB+1, 1), LDB) | |||
| * | |||
| * Pivot, P * B [ P * (L**T \ (T \ (L \P**T * B) )) ] | |||
| * Pivot, P * B -> B [ P * (L**T \ (T \ (L \P**T * B) )) ] | |||
| * | |||
| CALL ZLASWP( NRHS, B, LDB, NB+1, N, IPIV, -1 ) | |||
| * | |||
| @@ -67,7 +67,7 @@ | |||
| *> R * B**H + L * E**H = scale * -F | |||
| *> | |||
| *> This case is used to compute an estimate of Dif[(A, D), (B, E)] = | |||
| *> = sigma_min(Z) using reverse communicaton with ZLACON. | |||
| *> = sigma_min(Z) using reverse communication with ZLACON. | |||
| *> | |||
| *> ZTGSY2 also (IJOB >= 1) contributes to the computation in ZTGSYL | |||
| *> of an upper bound on the separation between to matrix pairs. Then | |||
| @@ -81,7 +81,7 @@ | |||
| *> \param[in] TRANS | |||
| *> \verbatim | |||
| *> TRANS is CHARACTER*1 | |||
| *> = 'N', solve the generalized Sylvester equation (1). | |||
| *> = 'N': solve the generalized Sylvester equation (1). | |||
| *> = 'T': solve the 'transposed' system (3). | |||
| *> \endverbatim | |||
| *> | |||
| @@ -94,7 +94,7 @@ | |||
| *> | |||
| *> \param[in] V | |||
| *> \verbatim | |||
| *> V is COMPLEX*16 array, dimension (LDA,K) | |||
| *> V is COMPLEX*16 array, dimension (LDV,K) | |||
| *> The i-th row must contain the vector which defines the | |||
| *> elementary reflector H(i), for i = 1,2,...,k, as returned by | |||
| *> DTPLQT in B. See Further Details. | |||
| @@ -94,7 +94,7 @@ | |||
| *> | |||
| *> \param[in] V | |||
| *> \verbatim | |||
| *> V is COMPLEX*16 array, dimension (LDA,K) | |||
| *> V is COMPLEX*16 array, dimension (LDV,K) | |||
| *> The i-th column must contain the vector which defines the | |||
| *> elementary reflector H(i), for i = 1,2,...,k, as returned by | |||
| *> CTPQRT in B. See Further Details. | |||
| @@ -152,8 +152,8 @@ | |||
| *> \verbatim | |||
| *> LDA is INTEGER | |||
| *> The leading dimension of the array A. | |||
| *> If SIDE = 'L', LDC >= max(1,K); | |||
| *> If SIDE = 'R', LDC >= max(1,M). | |||
| *> If SIDE = 'L', LDA >= max(1,K); | |||
| *> If SIDE = 'R', LDA >= max(1,M). | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in,out] B | |||
| @@ -0,0 +1,307 @@ | |||
| *> \brief \b ZUNGTSQR | |||
| * | |||
| * =========== DOCUMENTATION =========== | |||
| * | |||
| * Online html documentation available at | |||
| * http://www.netlib.org/lapack/explore-html/ | |||
| * | |||
| *> \htmlonly | |||
| *> Download ZUNGTSQR + dependencies | |||
| *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/zuntsqr.f"> | |||
| *> [TGZ]</a> | |||
| *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/zungtsqr.f"> | |||
| *> [ZIP]</a> | |||
| *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/zungtsqr.f"> | |||
| *> [TXT]</a> | |||
| *> | |||
| * Definition: | |||
| * =========== | |||
| * | |||
| * SUBROUTINE ZUNGTSQR( M, N, MB, NB, A, LDA, T, LDT, WORK, LWORK, | |||
| * $ INFO ) | |||
| * | |||
| * .. Scalar Arguments .. | |||
| * INTEGER INFO, LDA, LDT, LWORK, M, N, MB, NB | |||
| * .. | |||
| * .. Array Arguments .. | |||
| * COMPLEX*16 A( LDA, * ), T( LDT, * ), WORK( * ) | |||
| * .. | |||
| * | |||
| *> \par Purpose: | |||
| * ============= | |||
| *> | |||
| *> \verbatim | |||
| *> | |||
| *> ZUNGTSQR generates an M-by-N complex matrix Q_out with orthonormal | |||
| *> columns, which are the first N columns of a product of comlpex unitary | |||
| *> matrices of order M which are returned by ZLATSQR | |||
| *> | |||
| *> Q_out = first_N_columns_of( Q(1)_in * Q(2)_in * ... * Q(k)_in ). | |||
| *> | |||
| *> See the documentation for ZLATSQR. | |||
| *> \endverbatim | |||
| * | |||
| * Arguments: | |||
| * ========== | |||
| * | |||
| *> \param[in] M | |||
| *> \verbatim | |||
| *> M is INTEGER | |||
| *> The number of rows of the matrix A. M >= 0. | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in] N | |||
| *> \verbatim | |||
| *> N is INTEGER | |||
| *> The number of columns of the matrix A. M >= N >= 0. | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in] MB | |||
| *> \verbatim | |||
| *> MB is INTEGER | |||
| *> The row block size used by DLATSQR to return | |||
| *> arrays A and T. MB > N. | |||
| *> (Note that if MB > M, then M is used instead of MB | |||
| *> as the row block size). | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in] NB | |||
| *> \verbatim | |||
| *> NB is INTEGER | |||
| *> The column block size used by ZLATSQR to return | |||
| *> arrays A and T. NB >= 1. | |||
| *> (Note that if NB > N, then N is used instead of NB | |||
| *> as the column block size). | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in,out] A | |||
| *> \verbatim | |||
| *> A is COMPLEX*16 array, dimension (LDA,N) | |||
| *> | |||
| *> On entry: | |||
| *> | |||
| *> The elements on and above the diagonal are not accessed. | |||
| *> The elements below the diagonal represent the unit | |||
| *> lower-trapezoidal blocked matrix V computed by ZLATSQR | |||
| *> that defines the input matrices Q_in(k) (ones on the | |||
| *> diagonal are not stored) (same format as the output A | |||
| *> below the diagonal in ZLATSQR). | |||
| *> | |||
| *> On exit: | |||
| *> | |||
| *> The array A contains an M-by-N orthonormal matrix Q_out, | |||
| *> i.e the columns of A are orthogonal unit vectors. | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in] LDA | |||
| *> \verbatim | |||
| *> LDA is INTEGER | |||
| *> The leading dimension of the array A. LDA >= max(1,M). | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in] T | |||
| *> \verbatim | |||
| *> T is COMPLEX*16 array, | |||
| *> dimension (LDT, N * NIRB) | |||
| *> where NIRB = Number_of_input_row_blocks | |||
| *> = MAX( 1, CEIL((M-N)/(MB-N)) ) | |||
| *> Let NICB = Number_of_input_col_blocks | |||
| *> = CEIL(N/NB) | |||
| *> | |||
| *> The upper-triangular block reflectors used to define the | |||
| *> input matrices Q_in(k), k=(1:NIRB*NICB). The block | |||
| *> reflectors are stored in compact form in NIRB block | |||
| *> reflector sequences. Each of NIRB block reflector sequences | |||
| *> is stored in a larger NB-by-N column block of T and consists | |||
| *> of NICB smaller NB-by-NB upper-triangular column blocks. | |||
| *> (same format as the output T in ZLATSQR). | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in] LDT | |||
| *> \verbatim | |||
| *> LDT is INTEGER | |||
| *> The leading dimension of the array T. | |||
| *> LDT >= max(1,min(NB1,N)). | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[out] WORK | |||
| *> \verbatim | |||
| *> (workspace) COMPLEX*16 array, dimension (MAX(2,LWORK)) | |||
| *> On exit, if INFO = 0, WORK(1) returns the optimal LWORK. | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in] LWORK | |||
| *> \verbatim | |||
| *> The dimension of the array WORK. LWORK >= (M+NB)*N. | |||
| *> 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. | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[out] INFO | |||
| *> \verbatim | |||
| *> INFO is INTEGER | |||
| *> = 0: successful exit | |||
| *> < 0: if INFO = -i, the i-th argument had an illegal value | |||
| *> \endverbatim | |||
| *> | |||
| * Authors: | |||
| * ======== | |||
| * | |||
| *> \author Univ. of Tennessee | |||
| *> \author Univ. of California Berkeley | |||
| *> \author Univ. of Colorado Denver | |||
| *> \author NAG Ltd. | |||
| * | |||
| *> \date November 2019 | |||
| * | |||
| *> \ingroup comlex16OTHERcomputational | |||
| * | |||
| *> \par Contributors: | |||
| * ================== | |||
| *> | |||
| *> \verbatim | |||
| *> | |||
| *> November 2019, Igor Kozachenko, | |||
| *> Computer Science Division, | |||
| *> University of California, Berkeley | |||
| *> | |||
| *> \endverbatim | |||
| * | |||
| * ===================================================================== | |||
| SUBROUTINE ZUNGTSQR( M, N, MB, NB, A, LDA, T, LDT, WORK, LWORK, | |||
| $ INFO ) | |||
| IMPLICIT NONE | |||
| * | |||
| * -- LAPACK computational routine (version 3.9.0) -- | |||
| * -- LAPACK is a software package provided by Univ. of Tennessee, -- | |||
| * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- | |||
| * November 2019 | |||
| * | |||
| * .. Scalar Arguments .. | |||
| INTEGER INFO, LDA, LDT, LWORK, M, N, MB, NB | |||
| * .. | |||
| * .. Array Arguments .. | |||
| COMPLEX*16 A( LDA, * ), T( LDT, * ), WORK( * ) | |||
| * .. | |||
| * | |||
| * ===================================================================== | |||
| * | |||
| * .. Parameters .. | |||
| COMPLEX*16 CONE, CZERO | |||
| PARAMETER ( CONE = ( 1.0D+0, 0.0D+0 ), | |||
| $ CZERO = ( 0.0D+0, 0.0D+0 ) ) | |||
| * .. | |||
| * .. Local Scalars .. | |||
| LOGICAL LQUERY | |||
| INTEGER IINFO, LDC, LWORKOPT, LC, LW, NBLOCAL, J | |||
| * .. | |||
| * .. External Subroutines .. | |||
| EXTERNAL ZCOPY, ZLAMTSQR, ZLASET, XERBLA | |||
| * .. | |||
| * .. Intrinsic Functions .. | |||
| INTRINSIC DCMPLX, MAX, MIN | |||
| * .. | |||
| * .. Executable Statements .. | |||
| * | |||
| * Test the input parameters | |||
| * | |||
| LQUERY = LWORK.EQ.-1 | |||
| INFO = 0 | |||
| IF( M.LT.0 ) THEN | |||
| INFO = -1 | |||
| ELSE IF( N.LT.0 .OR. M.LT.N ) THEN | |||
| INFO = -2 | |||
| ELSE IF( MB.LE.N ) THEN | |||
| INFO = -3 | |||
| ELSE IF( NB.LT.1 ) THEN | |||
| INFO = -4 | |||
| ELSE IF( LDA.LT.MAX( 1, M ) ) THEN | |||
| INFO = -6 | |||
| ELSE IF( LDT.LT.MAX( 1, MIN( NB, N ) ) ) THEN | |||
| INFO = -8 | |||
| ELSE | |||
| * | |||
| * Test the input LWORK for the dimension of the array WORK. | |||
| * This workspace is used to store array C(LDC, N) and WORK(LWORK) | |||
| * in the call to ZLAMTSQR. See the documentation for ZLAMTSQR. | |||
| * | |||
| IF( LWORK.LT.2 .AND. (.NOT.LQUERY) ) THEN | |||
| INFO = -10 | |||
| ELSE | |||
| * | |||
| * Set block size for column blocks | |||
| * | |||
| NBLOCAL = MIN( NB, N ) | |||
| * | |||
| * LWORK = -1, then set the size for the array C(LDC,N) | |||
| * in ZLAMTSQR call and set the optimal size of the work array | |||
| * WORK(LWORK) in ZLAMTSQR call. | |||
| * | |||
| LDC = M | |||
| LC = LDC*N | |||
| LW = N * NBLOCAL | |||
| * | |||
| LWORKOPT = LC+LW | |||
| * | |||
| IF( ( LWORK.LT.MAX( 1, LWORKOPT ) ).AND.(.NOT.LQUERY) ) THEN | |||
| INFO = -10 | |||
| END IF | |||
| END IF | |||
| * | |||
| END IF | |||
| * | |||
| * Handle error in the input parameters and return workspace query. | |||
| * | |||
| IF( INFO.NE.0 ) THEN | |||
| CALL XERBLA( 'ZUNGTSQR', -INFO ) | |||
| RETURN | |||
| ELSE IF ( LQUERY ) THEN | |||
| WORK( 1 ) = DCMPLX( LWORKOPT ) | |||
| RETURN | |||
| END IF | |||
| * | |||
| * Quick return if possible | |||
| * | |||
| IF( MIN( M, N ).EQ.0 ) THEN | |||
| WORK( 1 ) = DCMPLX( LWORKOPT ) | |||
| RETURN | |||
| END IF | |||
| * | |||
| * (1) Form explicitly the tall-skinny M-by-N left submatrix Q1_in | |||
| * of M-by-M orthogonal matrix Q_in, which is implicitly stored in | |||
| * the subdiagonal part of input array A and in the input array T. | |||
| * Perform by the following operation using the routine ZLAMTSQR. | |||
| * | |||
| * Q1_in = Q_in * ( I ), where I is a N-by-N identity matrix, | |||
| * ( 0 ) 0 is a (M-N)-by-N zero matrix. | |||
| * | |||
| * (1a) Form M-by-N matrix in the array WORK(1:LDC*N) with ones | |||
| * on the diagonal and zeros elsewhere. | |||
| * | |||
| CALL ZLASET( 'F', M, N, CZERO, CONE, WORK, LDC ) | |||
| * | |||
| * (1b) On input, WORK(1:LDC*N) stores ( I ); | |||
| * ( 0 ) | |||
| * | |||
| * On output, WORK(1:LDC*N) stores Q1_in. | |||
| * | |||
| CALL ZLAMTSQR( 'L', 'N', M, N, N, MB, NBLOCAL, A, LDA, T, LDT, | |||
| $ WORK, LDC, WORK( LC+1 ), LW, IINFO ) | |||
| * | |||
| * (2) Copy the result from the part of the work array (1:M,1:N) | |||
| * with the leading dimension LDC that starts at WORK(1) into | |||
| * the output array A(1:M,1:N) column-by-column. | |||
| * | |||
| DO J = 1, N | |||
| CALL ZCOPY( M, WORK( (J-1)*LDC + 1 ), 1, A( 1, J ), 1 ) | |||
| END DO | |||
| * | |||
| WORK( 1 ) = DCMPLX( LWORKOPT ) | |||
| RETURN | |||
| * | |||
| * End of ZUNGTSQR | |||
| * | |||
| END | |||
| @@ -0,0 +1,441 @@ | |||
| *> \brief \b ZUNHR_COL | |||
| * | |||
| * =========== DOCUMENTATION =========== | |||
| * | |||
| * Online html documentation available at | |||
| * http://www.netlib.org/lapack/explore-html/ | |||
| * | |||
| *> \htmlonly | |||
| *> Download ZUNHR_COL + dependencies | |||
| *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/zunhr_col.f"> | |||
| *> [TGZ]</a> | |||
| *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/zunhr_col.f"> | |||
| *> [ZIP]</a> | |||
| *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/zunhr_col.f"> | |||
| *> [TXT]</a> | |||
| *> | |||
| * Definition: | |||
| * =========== | |||
| * | |||
| * SUBROUTINE ZUNHR_COL( M, N, NB, A, LDA, T, LDT, D, INFO ) | |||
| * | |||
| * .. Scalar Arguments .. | |||
| * INTEGER INFO, LDA, LDT, M, N, NB | |||
| * .. | |||
| * .. Array Arguments .. | |||
| * COMPLEX*16 A( LDA, * ), D( * ), T( LDT, * ) | |||
| * .. | |||
| * | |||
| *> \par Purpose: | |||
| * ============= | |||
| *> | |||
| *> \verbatim | |||
| *> | |||
| *> ZUNHR_COL takes an M-by-N complex matrix Q_in with orthonormal columns | |||
| *> as input, stored in A, and performs Householder Reconstruction (HR), | |||
| *> i.e. reconstructs Householder vectors V(i) implicitly representing | |||
| *> another M-by-N matrix Q_out, with the property that Q_in = Q_out*S, | |||
| *> where S is an N-by-N diagonal matrix with diagonal entries | |||
| *> equal to +1 or -1. The Householder vectors (columns V(i) of V) are | |||
| *> stored in A on output, and the diagonal entries of S are stored in D. | |||
| *> Block reflectors are also returned in T | |||
| *> (same output format as ZGEQRT). | |||
| *> \endverbatim | |||
| * | |||
| * Arguments: | |||
| * ========== | |||
| * | |||
| *> \param[in] M | |||
| *> \verbatim | |||
| *> M is INTEGER | |||
| *> The number of rows of the matrix A. M >= 0. | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in] N | |||
| *> \verbatim | |||
| *> N is INTEGER | |||
| *> The number of columns of the matrix A. M >= N >= 0. | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in] NB | |||
| *> \verbatim | |||
| *> NB is INTEGER | |||
| *> The column block size to be used in the reconstruction | |||
| *> of Householder column vector blocks in the array A and | |||
| *> corresponding block reflectors in the array T. NB >= 1. | |||
| *> (Note that if NB > N, then N is used instead of NB | |||
| *> as the column block size.) | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in,out] A | |||
| *> \verbatim | |||
| *> A is COMPLEX*16 array, dimension (LDA,N) | |||
| *> | |||
| *> On entry: | |||
| *> | |||
| *> The array A contains an M-by-N orthonormal matrix Q_in, | |||
| *> i.e the columns of A are orthogonal unit vectors. | |||
| *> | |||
| *> On exit: | |||
| *> | |||
| *> The elements below the diagonal of A represent the unit | |||
| *> lower-trapezoidal matrix V of Householder column vectors | |||
| *> V(i). The unit diagonal entries of V are not stored | |||
| *> (same format as the output below the diagonal in A from | |||
| *> ZGEQRT). The matrix T and the matrix V stored on output | |||
| *> in A implicitly define Q_out. | |||
| *> | |||
| *> The elements above the diagonal contain the factor U | |||
| *> of the "modified" LU-decomposition: | |||
| *> Q_in - ( S ) = V * U | |||
| *> ( 0 ) | |||
| *> where 0 is a (M-N)-by-(M-N) zero matrix. | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in] LDA | |||
| *> \verbatim | |||
| *> LDA is INTEGER | |||
| *> The leading dimension of the array A. LDA >= max(1,M). | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[out] T | |||
| *> \verbatim | |||
| *> T is COMPLEX*16 array, | |||
| *> dimension (LDT, N) | |||
| *> | |||
| *> Let NOCB = Number_of_output_col_blocks | |||
| *> = CEIL(N/NB) | |||
| *> | |||
| *> On exit, T(1:NB, 1:N) contains NOCB upper-triangular | |||
| *> block reflectors used to define Q_out stored in compact | |||
| *> form as a sequence of upper-triangular NB-by-NB column | |||
| *> blocks (same format as the output T in ZGEQRT). | |||
| *> The matrix T and the matrix V stored on output in A | |||
| *> implicitly define Q_out. NOTE: The lower triangles | |||
| *> below the upper-triangular blcoks will be filled with | |||
| *> zeros. See Further Details. | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[in] LDT | |||
| *> \verbatim | |||
| *> LDT is INTEGER | |||
| *> The leading dimension of the array T. | |||
| *> LDT >= max(1,min(NB,N)). | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[out] D | |||
| *> \verbatim | |||
| *> D is COMPLEX*16 array, dimension min(M,N). | |||
| *> The elements can be only plus or minus one. | |||
| *> | |||
| *> D(i) is constructed as D(i) = -SIGN(Q_in_i(i,i)), where | |||
| *> 1 <= i <= min(M,N), and Q_in_i is Q_in after performing | |||
| *> i-1 steps of “modified” Gaussian elimination. | |||
| *> See Further Details. | |||
| *> \endverbatim | |||
| *> | |||
| *> \param[out] INFO | |||
| *> \verbatim | |||
| *> INFO is INTEGER | |||
| *> = 0: successful exit | |||
| *> < 0: if INFO = -i, the i-th argument had an illegal value | |||
| *> \endverbatim | |||
| *> | |||
| *> \par Further Details: | |||
| * ===================== | |||
| *> | |||
| *> \verbatim | |||
| *> | |||
| *> The computed M-by-M unitary factor Q_out is defined implicitly as | |||
| *> a product of unitary matrices Q_out(i). Each Q_out(i) is stored in | |||
| *> the compact WY-representation format in the corresponding blocks of | |||
| *> matrices V (stored in A) and T. | |||
| *> | |||
| *> The M-by-N unit lower-trapezoidal matrix V stored in the M-by-N | |||
| *> matrix A contains the column vectors V(i) in NB-size column | |||
| *> blocks VB(j). For example, VB(1) contains the columns | |||
| *> V(1), V(2), ... V(NB). NOTE: The unit entries on | |||
| *> the diagonal of Y are not stored in A. | |||
| *> | |||
| *> The number of column blocks is | |||
| *> | |||
| *> NOCB = Number_of_output_col_blocks = CEIL(N/NB) | |||
| *> | |||
| *> where each block is of order NB except for the last block, which | |||
| *> is of order LAST_NB = N - (NOCB-1)*NB. | |||
| *> | |||
| *> For example, if M=6, N=5 and NB=2, the matrix V is | |||
| *> | |||
| *> | |||
| *> V = ( VB(1), VB(2), VB(3) ) = | |||
| *> | |||
| *> = ( 1 ) | |||
| *> ( v21 1 ) | |||
| *> ( v31 v32 1 ) | |||
| *> ( v41 v42 v43 1 ) | |||
| *> ( v51 v52 v53 v54 1 ) | |||
| *> ( v61 v62 v63 v54 v65 ) | |||
| *> | |||
| *> | |||
| *> For each of the column blocks VB(i), an upper-triangular block | |||
| *> reflector TB(i) is computed. These blocks are stored as | |||
| *> a sequence of upper-triangular column blocks in the NB-by-N | |||
| *> matrix T. The size of each TB(i) block is NB-by-NB, except | |||
| *> for the last block, whose size is LAST_NB-by-LAST_NB. | |||
| *> | |||
| *> For example, if M=6, N=5 and NB=2, the matrix T is | |||
| *> | |||
| *> T = ( TB(1), TB(2), TB(3) ) = | |||
| *> | |||
| *> = ( t11 t12 t13 t14 t15 ) | |||
| *> ( t22 t24 ) | |||
| *> | |||
| *> | |||
| *> The M-by-M factor Q_out is given as a product of NOCB | |||
| *> unitary M-by-M matrices Q_out(i). | |||
| *> | |||
| *> Q_out = Q_out(1) * Q_out(2) * ... * Q_out(NOCB), | |||
| *> | |||
| *> where each matrix Q_out(i) is given by the WY-representation | |||
| *> using corresponding blocks from the matrices V and T: | |||
| *> | |||
| *> Q_out(i) = I - VB(i) * TB(i) * (VB(i))**T, | |||
| *> | |||
| *> where I is the identity matrix. Here is the formula with matrix | |||
| *> dimensions: | |||
| *> | |||
| *> Q(i){M-by-M} = I{M-by-M} - | |||
| *> VB(i){M-by-INB} * TB(i){INB-by-INB} * (VB(i))**T {INB-by-M}, | |||
| *> | |||
| *> where INB = NB, except for the last block NOCB | |||
| *> for which INB=LAST_NB. | |||
| *> | |||
| *> ===== | |||
| *> NOTE: | |||
| *> ===== | |||
| *> | |||
| *> If Q_in is the result of doing a QR factorization | |||
| *> B = Q_in * R_in, then: | |||
| *> | |||
| *> B = (Q_out*S) * R_in = Q_out * (S * R_in) = O_out * R_out. | |||
| *> | |||
| *> So if one wants to interpret Q_out as the result | |||
| *> of the QR factorization of B, then corresponding R_out | |||
| *> should be obtained by R_out = S * R_in, i.e. some rows of R_in | |||
| *> should be multiplied by -1. | |||
| *> | |||
| *> For the details of the algorithm, see [1]. | |||
| *> | |||
| *> [1] "Reconstructing Householder vectors from tall-skinny QR", | |||
| *> G. Ballard, J. Demmel, L. Grigori, M. Jacquelin, H.D. Nguyen, | |||
| *> E. Solomonik, J. Parallel Distrib. Comput., | |||
| *> vol. 85, pp. 3-31, 2015. | |||
| *> \endverbatim | |||
| *> | |||
| * Authors: | |||
| * ======== | |||
| * | |||
| *> \author Univ. of Tennessee | |||
| *> \author Univ. of California Berkeley | |||
| *> \author Univ. of Colorado Denver | |||
| *> \author NAG Ltd. | |||
| * | |||
| *> \date November 2019 | |||
| * | |||
| *> \ingroup complex16OTHERcomputational | |||
| * | |||
| *> \par Contributors: | |||
| * ================== | |||
| *> | |||
| *> \verbatim | |||
| *> | |||
| *> November 2019, Igor Kozachenko, | |||
| *> Computer Science Division, | |||
| *> University of California, Berkeley | |||
| *> | |||
| *> \endverbatim | |||
| * | |||
| * ===================================================================== | |||
| SUBROUTINE ZUNHR_COL( M, N, NB, A, LDA, T, LDT, D, INFO ) | |||
| IMPLICIT NONE | |||
| * | |||
| * -- LAPACK computational routine (version 3.9.0) -- | |||
| * -- LAPACK is a software package provided by Univ. of Tennessee, -- | |||
| * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- | |||
| * November 2019 | |||
| * | |||
| * .. Scalar Arguments .. | |||
| INTEGER INFO, LDA, LDT, M, N, NB | |||
| * .. | |||
| * .. Array Arguments .. | |||
| COMPLEX*16 A( LDA, * ), D( * ), T( LDT, * ) | |||
| * .. | |||
| * | |||
| * ===================================================================== | |||
| * | |||
| * .. Parameters .. | |||
| COMPLEX*16 CONE, CZERO | |||
| PARAMETER ( CONE = ( 1.0D+0, 0.0D+0 ), | |||
| $ CZERO = ( 0.0D+0, 0.0D+0 ) ) | |||
| * .. | |||
| * .. Local Scalars .. | |||
| INTEGER I, IINFO, J, JB, JBTEMP1, JBTEMP2, JNB, | |||
| $ NPLUSONE | |||
| * .. | |||
| * .. External Subroutines .. | |||
| EXTERNAL ZCOPY, ZLAUNHR_COL_GETRFNP, ZSCAL, ZTRSM, | |||
| $ XERBLA | |||
| * .. | |||
| * .. Intrinsic Functions .. | |||
| INTRINSIC MAX, MIN | |||
| * .. | |||
| * .. Executable Statements .. | |||
| * | |||
| * Test the input parameters | |||
| * | |||
| INFO = 0 | |||
| IF( M.LT.0 ) THEN | |||
| INFO = -1 | |||
| ELSE IF( N.LT.0 .OR. N.GT.M ) THEN | |||
| INFO = -2 | |||
| ELSE IF( NB.LT.1 ) THEN | |||
| INFO = -3 | |||
| ELSE IF( LDA.LT.MAX( 1, M ) ) THEN | |||
| INFO = -5 | |||
| ELSE IF( LDT.LT.MAX( 1, MIN( NB, N ) ) ) THEN | |||
| INFO = -7 | |||
| END IF | |||
| * | |||
| * Handle error in the input parameters. | |||
| * | |||
| IF( INFO.NE.0 ) THEN | |||
| CALL XERBLA( 'ZUNHR_COL', -INFO ) | |||
| RETURN | |||
| END IF | |||
| * | |||
| * Quick return if possible | |||
| * | |||
| IF( MIN( M, N ).EQ.0 ) THEN | |||
| RETURN | |||
| END IF | |||
| * | |||
| * On input, the M-by-N matrix A contains the unitary | |||
| * M-by-N matrix Q_in. | |||
| * | |||
| * (1) Compute the unit lower-trapezoidal V (ones on the diagonal | |||
| * are not stored) by performing the "modified" LU-decomposition. | |||
| * | |||
| * Q_in - ( S ) = V * U = ( V1 ) * U, | |||
| * ( 0 ) ( V2 ) | |||
| * | |||
| * where 0 is an (M-N)-by-N zero matrix. | |||
| * | |||
| * (1-1) Factor V1 and U. | |||
| CALL ZLAUNHR_COL_GETRFNP( N, N, A, LDA, D, IINFO ) | |||
| * | |||
| * (1-2) Solve for V2. | |||
| * | |||
| IF( M.GT.N ) THEN | |||
| CALL ZTRSM( 'R', 'U', 'N', 'N', M-N, N, CONE, A, LDA, | |||
| $ A( N+1, 1 ), LDA ) | |||
| END IF | |||
| * | |||
| * (2) Reconstruct the block reflector T stored in T(1:NB, 1:N) | |||
| * as a sequence of upper-triangular blocks with NB-size column | |||
| * blocking. | |||
| * | |||
| * Loop over the column blocks of size NB of the array A(1:M,1:N) | |||
| * and the array T(1:NB,1:N), JB is the column index of a column | |||
| * block, JNB is the column block size at each step JB. | |||
| * | |||
| NPLUSONE = N + 1 | |||
| DO JB = 1, N, NB | |||
| * | |||
| * (2-0) Determine the column block size JNB. | |||
| * | |||
| JNB = MIN( NPLUSONE-JB, NB ) | |||
| * | |||
| * (2-1) Copy the upper-triangular part of the current JNB-by-JNB | |||
| * diagonal block U(JB) (of the N-by-N matrix U) stored | |||
| * in A(JB:JB+JNB-1,JB:JB+JNB-1) into the upper-triangular part | |||
| * of the current JNB-by-JNB block T(1:JNB,JB:JB+JNB-1) | |||
| * column-by-column, total JNB*(JNB+1)/2 elements. | |||
| * | |||
| JBTEMP1 = JB - 1 | |||
| DO J = JB, JB+JNB-1 | |||
| CALL ZCOPY( J-JBTEMP1, A( JB, J ), 1, T( 1, J ), 1 ) | |||
| END DO | |||
| * | |||
| * (2-2) Perform on the upper-triangular part of the current | |||
| * JNB-by-JNB diagonal block U(JB) (of the N-by-N matrix U) stored | |||
| * in T(1:JNB,JB:JB+JNB-1) the following operation in place: | |||
| * (-1)*U(JB)*S(JB), i.e the result will be stored in the upper- | |||
| * triangular part of T(1:JNB,JB:JB+JNB-1). This multiplication | |||
| * of the JNB-by-JNB diagonal block U(JB) by the JNB-by-JNB | |||
| * diagonal block S(JB) of the N-by-N sign matrix S from the | |||
| * right means changing the sign of each J-th column of the block | |||
| * U(JB) according to the sign of the diagonal element of the block | |||
| * S(JB), i.e. S(J,J) that is stored in the array element D(J). | |||
| * | |||
| DO J = JB, JB+JNB-1 | |||
| IF( D( J ).EQ.CONE ) THEN | |||
| CALL ZSCAL( J-JBTEMP1, -CONE, T( 1, J ), 1 ) | |||
| END IF | |||
| END DO | |||
| * | |||
| * (2-3) Perform the triangular solve for the current block | |||
| * matrix X(JB): | |||
| * | |||
| * X(JB) * (A(JB)**T) = B(JB), where: | |||
| * | |||
| * A(JB)**T is a JNB-by-JNB unit upper-triangular | |||
| * coefficient block, and A(JB)=V1(JB), which | |||
| * is a JNB-by-JNB unit lower-triangular block | |||
| * stored in A(JB:JB+JNB-1,JB:JB+JNB-1). | |||
| * The N-by-N matrix V1 is the upper part | |||
| * of the M-by-N lower-trapezoidal matrix V | |||
| * stored in A(1:M,1:N); | |||
| * | |||
| * B(JB) is a JNB-by-JNB upper-triangular right-hand | |||
| * side block, B(JB) = (-1)*U(JB)*S(JB), and | |||
| * B(JB) is stored in T(1:JNB,JB:JB+JNB-1); | |||
| * | |||
| * X(JB) is a JNB-by-JNB upper-triangular solution | |||
| * block, X(JB) is the upper-triangular block | |||
| * reflector T(JB), and X(JB) is stored | |||
| * in T(1:JNB,JB:JB+JNB-1). | |||
| * | |||
| * In other words, we perform the triangular solve for the | |||
| * upper-triangular block T(JB): | |||
| * | |||
| * T(JB) * (V1(JB)**T) = (-1)*U(JB)*S(JB). | |||
| * | |||
| * Even though the blocks X(JB) and B(JB) are upper- | |||
| * triangular, the routine ZTRSM will access all JNB**2 | |||
| * elements of the square T(1:JNB,JB:JB+JNB-1). Therefore, | |||
| * we need to set to zero the elements of the block | |||
| * T(1:JNB,JB:JB+JNB-1) below the diagonal before the call | |||
| * to ZTRSM. | |||
| * | |||
| * (2-3a) Set the elements to zero. | |||
| * | |||
| JBTEMP2 = JB - 2 | |||
| DO J = JB, JB+JNB-2 | |||
| DO I = J-JBTEMP2, NB | |||
| T( I, J ) = CZERO | |||
| END DO | |||
| END DO | |||
| * | |||
| * (2-3b) Perform the triangular solve. | |||
| * | |||
| CALL ZTRSM( 'R', 'L', 'C', 'U', JNB, JNB, CONE, | |||
| $ A( JB, JB ), LDA, T( 1, JB ), LDT ) | |||
| * | |||
| END DO | |||
| * | |||
| RETURN | |||
| * | |||
| * End of ZUNHR_COL | |||
| * | |||
| END | |||