*> \brief \b CLAPMT performs a forward or backward permutation of the columns of a matrix. * * =========== DOCUMENTATION =========== * * Online html documentation available at * http://www.netlib.org/lapack/explore-html/ * *> \htmlonly *> Download CLAPMT + dependencies *> *> [TGZ] *> *> [ZIP] *> *> [TXT] *> \endhtmlonly * * Definition: * =========== * * SUBROUTINE CLAPMT( FORWRD, M, N, X, LDX, K ) * * .. Scalar Arguments .. * LOGICAL FORWRD * INTEGER LDX, M, N * .. * .. Array Arguments .. * INTEGER K( * ) * COMPLEX X( LDX, * ) * .. * * *> \par Purpose: * ============= *> *> \verbatim *> *> CLAPMT rearranges the columns of the M by N matrix X as specified *> by the permutation K(1),K(2),...,K(N) of the integers 1,...,N. *> If FORWRD = .TRUE., forward permutation: *> *> X(*,K(J)) is moved X(*,J) for J = 1,2,...,N. *> *> If FORWRD = .FALSE., backward permutation: *> *> X(*,J) is moved to X(*,K(J)) for J = 1,2,...,N. *> \endverbatim * * Arguments: * ========== * *> \param[in] FORWRD *> \verbatim *> FORWRD is LOGICAL *> = .TRUE., forward permutation *> = .FALSE., backward permutation *> \endverbatim *> *> \param[in] M *> \verbatim *> M is INTEGER *> The number of rows of the matrix X. M >= 0. *> \endverbatim *> *> \param[in] N *> \verbatim *> N is INTEGER *> The number of columns of the matrix X. N >= 0. *> \endverbatim *> *> \param[in,out] X *> \verbatim *> X is COMPLEX array, dimension (LDX,N) *> On entry, the M by N matrix X. *> On exit, X contains the permuted matrix X. *> \endverbatim *> *> \param[in] LDX *> \verbatim *> LDX is INTEGER *> The leading dimension of the array X, LDX >= MAX(1,M). *> \endverbatim *> *> \param[in,out] K *> \verbatim *> K is INTEGER array, dimension (N) *> On entry, K contains the permutation vector. K is used as *> internal workspace, but reset to its original value on *> output. *> \endverbatim * * Authors: * ======== * *> \author Univ. of Tennessee *> \author Univ. of California Berkeley *> \author Univ. of Colorado Denver *> \author NAG Ltd. * *> \ingroup complexOTHERauxiliary * * ===================================================================== SUBROUTINE CLAPMT( FORWRD, M, N, X, LDX, K ) * * -- LAPACK auxiliary routine -- * -- LAPACK is a software package provided by Univ. of Tennessee, -- * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- * * .. Scalar Arguments .. LOGICAL FORWRD INTEGER LDX, M, N * .. * .. Array Arguments .. INTEGER K( * ) COMPLEX X( LDX, * ) * .. * * ===================================================================== * * .. Local Scalars .. INTEGER I, II, J, IN COMPLEX TEMP * .. * .. Executable Statements .. * IF( N.LE.1 ) \$ RETURN * DO 10 I = 1, N K( I ) = -K( I ) 10 CONTINUE * IF( FORWRD ) THEN * * Forward permutation * DO 60 I = 1, N * IF( K( I ).GT.0 ) \$ GO TO 40 * J = I K( J ) = -K( J ) IN = K( J ) * 20 CONTINUE IF( K( IN ).GT.0 ) \$ GO TO 40 * DO 30 II = 1, M TEMP = X( II, J ) X( II, J ) = X( II, IN ) X( II, IN ) = TEMP 30 CONTINUE * K( IN ) = -K( IN ) J = IN IN = K( IN ) GO TO 20 * 40 CONTINUE * 60 CONTINUE * ELSE * * Backward permutation * DO 110 I = 1, N * IF( K( I ).GT.0 ) \$ GO TO 100 * K( I ) = -K( I ) J = K( I ) 80 CONTINUE IF( J.EQ.I ) \$ GO TO 100 * DO 90 II = 1, M TEMP = X( II, I ) X( II, I ) = X( II, J ) X( II, J ) = TEMP 90 CONTINUE * K( J ) = -K( J ) J = K( J ) GO TO 80 * 100 CONTINUE 110 CONTINUE * END IF * RETURN * * End of CLAPMT * END