*
*
SUBROUTINE PCSEPCHK( MS, NV, A, IA, JA, DESCA, EPSNORMA, THRESH,
$ Q, IQ, JQ, DESCQ, C, IC, JC, DESCC, W, WORK,
$ LWORK, TSTNRM, RESULT )
*
* -- ScaLAPACK routine (version 2.0.2) --
* Univ. of Tennessee, Univ. of California Berkeley, Univ. of Colorado Denver
* May 1 2012
*
* .. Scalar Arguments ..
INTEGER IA, IC, IQ, JA, JC, JQ, LWORK, MS, NV, RESULT
REAL EPSNORMA, THRESH, TSTNRM
* ..
* .. Array Arguments ..
*
INTEGER DESCA( * ), DESCC( * ), DESCQ( * )
REAL W( * ), WORK( * )
COMPLEX A( * ), C( * ), Q( * )
* ..
*
* Purpose
* =======
*
* Compute |AQ- QL| / (EPSNORMA * N)
* where EPSNORMA = (abstol + eps)*norm(A) when called by pdsqpsubtst.
*
* Notes
* =====
*
*
* Each global data object is described by an associated description
* vector. This vector stores the information required to establish
* the mapping between an object element and its corresponding process
* and memory location.
*
* Let A be a generic term for any 2D block cyclicly distributed array.
* Such a global array has an associated description vector DESCA.
* In the following comments, the character _ should be read as
* "of the global array".
*
* NOTATION STORED IN EXPLANATION
* --------------- -------------- --------------------------------------
* DTYPE_A(global) DESCA( DTYPE_ )The descriptor type. In this case,
* DTYPE_A = 1.
* CTXT_A (global) DESCA( CTXT_ ) The BLACS context handle, indicating
* the BLACS process grid A is distribu-
* ted over. The context itself is glo-
* bal, but the handle (the integer
* value) may vary.
* M_A (global) DESCA( M_ ) The number of rows in the global
* array A.
* N_A (global) DESCA( N_ ) The number of columns in the global
* array A.
* MB_A (global) DESCA( MB_ ) The blocking factor used to distribute
* the rows of the array.
* NB_A (global) DESCA( NB_ ) The blocking factor used to distribute
* the columns of the array.
* RSRC_A (global) DESCA( RSRC_ ) The process row over which the first
* row of the array A is distributed.
* CSRC_A (global) DESCA( CSRC_ ) The process column over which the
* first column of the array A is
* distributed.
* LLD_A (local) DESCA( LLD_ ) The leading dimension of the local
* array. LLD_A >= MAX(1,LOCr(M_A)).
*
* Let K be the number of rows or columns of a distributed matrix,
* and assume that its process grid has dimension p x q.
* LOCr( K ) denotes the number of elements of K that a process
* would receive if K were distributed over the p processes of its
* process column.
* Similarly, LOCc( K ) denotes the number of elements of K that a
* process would receive if K were distributed over the q processes of
* its process row.
* The values of LOCr() and LOCc() may be determined via a call to the
* ScaLAPACK tool function, NUMROC:
* LOCr( M ) = NUMROC( M, MB_A, MYROW, RSRC_A, NPROW ),
* LOCc( N ) = NUMROC( N, NB_A, MYCOL, CSRC_A, NPCOL ).
* An upper bound for these quantities may be computed by:
* LOCr( M ) <= ceil( ceil(M/MB_A)/NPROW )*MB_A
* LOCc( N ) <= ceil( ceil(N/NB_A)/NPCOL )*NB_A
*
*
* Arguments
* =========
*
* MP = number of local rows in A, C and Q
* MQ = number of local columns in A
* NQ = number of local columns in C and Q
*
* MS (global input) INTEGER
* Matrix size.
* The number of global rows in A, C and Q
* Also, the number of global columns in A
*
* NV (global input) INTEGER
* Number of eigenvectors
* The number of global columns in C and Q.
*
* A (local input) COMPLEX pointer to an
* array in local memory of dimension (LLD_A, LOCc(JA+N-1)).
* This array contains the local pieces of the MS-by-MS
* distributed test matrix A
*
* IA (global input) INTEGER
* A's global row index, which points to the beginning of the
* submatrix which is to be operated on.
*
* JA (global input) INTEGER
* A's global column index, which points to the beginning of
* the submatrix which is to be operated on.
*
* DESCA (global and local input) INTEGER array of dimension DLEN_.
* The array descriptor for the distributed matrix A.
*
* EPSNORMA (input) REAL
* abstol + eps * inf.norm(A)
* Abstol is absolute tolerence for the eigenvalues and is set
* in the calling routines, pdsepsubtst and pdsqpsubtst.
*
* THRESH (input) REAL
* A test will count as "failed" if the "error", computed as
* described below, exceeds THRESH. Note that the error
* is scaled to be O(1), so THRESH should be a reasonably
* small multiple of 1, e.g., 10 or 100. In particular,
* it should not depend on the precision (single vs. double)
* or the size of the matrix. It must be at least zero.
*
* Q (local input) COMPLEX array
* global dimension (MS, NV), local dimension (DESCA(DLEN_), NQ)
*
* Contains the eigenvectors as computed by PCHEEVX
*
* IQ (global input) INTEGER
* Q's global row index, which points to the beginning of the
* submatrix which is to be operated on.
*
* JQ (global input) INTEGER
* Q's global column index, which points to the beginning of
* the submatrix which is to be operated on.
*
* DESCQ (global and local input) INTEGER array of dimension DLEN_.
* The array descriptor for the distributed matrix Q.
*
* C (local workspace) COMPLEX array,
* global dimension (NV, NV), local dimension (DESCA(DLEN_), MQ)
*
* Accumulator for computing AQ -QL
*
* IC (global input) INTEGER
* C's global row index, which points to the beginning of the
* submatrix which is to be operated on.
*
* JC (global input) INTEGER
* C's global column index, which points to the beginning of
* the submatrix which is to be operated on.
*
* DESCC (global and local input) INTEGER array of dimension DLEN_.
* The array descriptor for the distributed matrix C.
*
* W (global input) REAL array, dimension (NV)
*
* Contains the computed eigenvalues
*
* WORK (local workspace) REAL array,
* dimension (LWORK)
*
* LWORK (local input) INTEGER
* The length of the array WORK.
* LWORK >= NUMROC( NV, DESCA( NB_ ), MYCOL, 0, NPCOL )
*
* TSTNRM (global output) REAL
* |AQ- QL| / ( EPSNROMA * MS )
*
* RESULT (global output) INTEGER
* 0 if the test passes i.e.
* |AQ -QL| / (abstol + eps * norm(A) ) <= n* THRESH
* 1 if the test fails i.e.
* |AQ -QL| / (abstol + eps * norm(A) ) > n * THRESH
*
* .. Local Scalars ..
*
INTEGER INFO, J, LOCALCOL, MP, MYCOL, MYROW, NPCOL,
$ NPROW, NQ, PCOL
REAL NORM
* ..
* .. Parameters ..
INTEGER BLOCK_CYCLIC_2D, DLEN_, DTYPE_, CTXT_, M_, N_,
$ MB_, NB_, RSRC_, CSRC_, LLD_
PARAMETER ( BLOCK_CYCLIC_2D = 1, DLEN_ = 9, DTYPE_ = 1,
$ CTXT_ = 2, M_ = 3, N_ = 4, MB_ = 5, NB_ = 6,
$ RSRC_ = 7, CSRC_ = 8, LLD_ = 9 )
COMPLEX ONE, NEGONE
PARAMETER ( ONE = 1.0E+0, NEGONE = -1.0E+0 )
* ..
* .. External Functions ..
INTEGER INDXG2L, INDXG2P, NUMROC
REAL PCLANGE
EXTERNAL INDXG2L, INDXG2P, NUMROC, PCLANGE
* ..
* .. External Subroutines ..
EXTERNAL BLACS_GRIDINFO, CHK1MAT, CLACPY, CSSCAL,
$ PCGEMM, PXERBLA
* ..
* .. Intrinsic Functions ..
INTRINSIC MAX
* ..
* .. Executable Statements ..
* This is just to keep ftnchek happy
IF( BLOCK_CYCLIC_2D*CSRC_*CTXT_*DLEN_*DTYPE_*LLD_*MB_*M_*NB_*N_*
$ RSRC_.LT.0 )RETURN
*
RESULT = 0
*
CALL BLACS_GRIDINFO( DESCA( CTXT_ ), NPROW, NPCOL, MYROW, MYCOL )
*
INFO = 0
CALL CHK1MAT( MS, 1, MS, 1, IA, JA, DESCA, 6, INFO )
CALL CHK1MAT( MS, 1, NV, 2, IQ, JQ, DESCQ, 12, INFO )
CALL CHK1MAT( MS, 1, NV, 2, IC, JC, DESCC, 16, INFO )
*
IF( INFO.EQ.0 ) THEN
*
MP = NUMROC( MS, DESCA( MB_ ), MYROW, 0, NPROW )
NQ = NUMROC( NV, DESCA( NB_ ), MYCOL, 0, NPCOL )
*
IF( IQ.NE.1 ) THEN
INFO = -10
ELSE IF( JQ.NE.1 ) THEN
INFO = -11
ELSE IF( IA.NE.1 ) THEN
INFO = -4
ELSE IF( JA.NE.1 ) THEN
INFO = -5
ELSE IF( IC.NE.1 ) THEN
INFO = -14
ELSE IF( JC.NE.1 ) THEN
INFO = -15
ELSE IF( LWORK.LT.NQ ) THEN
INFO = -19
END IF
END IF
*
IF( INFO.NE.0 ) THEN
CALL PXERBLA( DESCA( CTXT_ ), 'PCSEPCHK', -INFO )
RETURN
END IF
*
* C = Q * W
*
CALL CLACPY( 'A', MP, NQ, Q, DESCQ( LLD_ ), C, DESCC( LLD_ ) )
*
*
DO 10 J = 1, NV
PCOL = INDXG2P( J, DESCC( NB_ ), 0, 0, NPCOL )
LOCALCOL = INDXG2L( J, DESCC( NB_ ), 0, 0, NPCOL )
*
IF( MYCOL.EQ.PCOL ) THEN
CALL CSSCAL( MP, W( J ), C( ( LOCALCOL-1 )*DESCC( LLD_ )+
$ 1 ), 1 )
END IF
10 CONTINUE
*
*
* C = C - A * Q
*
CALL PCGEMM( 'N', 'N', MS, NV, MS, NEGONE, A, 1, 1, DESCA, Q, 1,
$ 1, DESCQ, ONE, C, 1, 1, DESCC )
*
* Compute the norm of C
*
*
NORM = PCLANGE( 'M', MS, NV, C, 1, 1, DESCC, WORK )
*
*
TSTNRM = NORM / EPSNORMA / MAX( MS, 1 )
*
IF( TSTNRM.GT.THRESH .OR. ( TSTNRM-TSTNRM.NE.0.0E0 ) ) THEN
RESULT = 1
END IF
*
*
RETURN
*
* End of PCSEPCHK
*
END