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SUBROUTINE CLACRM( M, N, A, LDA, B, LDB, C, LDC, RWORK )
*
* -- LAPACK auxiliary routine (version 3.1) --
* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
* November 2006
*
* .. Scalar Arguments ..
INTEGER LDA, LDB, LDC, M, N
* ..
* .. Array Arguments ..
REAL B( LDB, * ), RWORK( * )
COMPLEX A( LDA, * ), C( LDC, * )
* ..
*
* Purpose
* =======
*
* CLACRM performs a very simple matrix-matrix multiplication:
* C := A * B,
* where A is M by N and complex; B is N by N and real;
* C is M by N and complex.
*
* Arguments
* =========
*
* M (input) INTEGER
* The number of rows of the matrix A and of the matrix C.
* M >= 0.
*
* N (input) INTEGER
* The number of columns and rows of the matrix B and
* the number of columns of the matrix C.
* N >= 0.
*
* A (input) COMPLEX array, dimension (LDA, N)
* A contains the M by N matrix A.
*
* LDA (input) INTEGER
* The leading dimension of the array A. LDA >=max(1,M).
*
* B (input) REAL array, dimension (LDB, N)
* B contains the N by N matrix B.
*
* LDB (input) INTEGER
* The leading dimension of the array B. LDB >=max(1,N).
*
* C (input) COMPLEX array, dimension (LDC, N)
* C contains the M by N matrix C.
*
* LDC (input) INTEGER
* The leading dimension of the array C. LDC >=max(1,N).
*
* RWORK (workspace) REAL array, dimension (2*M*N)
*
* =====================================================================
*
* .. Parameters ..
REAL ONE, ZERO
PARAMETER ( ONE = 1.0E0, ZERO = 0.0E0 )
* ..
* .. Local Scalars ..
INTEGER I, J, L
* ..
* .. Intrinsic Functions ..
INTRINSIC AIMAG, CMPLX, REAL
* ..
* .. External Subroutines ..
EXTERNAL SGEMM
* ..
* .. Executable Statements ..
*
* Quick return if possible.
*
IF( ( M.EQ.0 ) .OR. ( N.EQ.0 ) )
$ RETURN
*
DO 20 J = 1, N
DO 10 I = 1, M
RWORK( ( J-1 )*M+I ) = REAL( A( I, J ) )
10 CONTINUE
20 CONTINUE
*
L = M*N + 1
CALL SGEMM( 'N', 'N', M, N, N, ONE, RWORK, M, B, LDB, ZERO,
$ RWORK( L ), M )
DO 40 J = 1, N
DO 30 I = 1, M
C( I, J ) = RWORK( L+( J-1 )*M+I-1 )
30 CONTINUE
40 CONTINUE
*
DO 60 J = 1, N
DO 50 I = 1, M
RWORK( ( J-1 )*M+I ) = AIMAG( A( I, J ) )
50 CONTINUE
60 CONTINUE
CALL SGEMM( 'N', 'N', M, N, N, ONE, RWORK, M, B, LDB, ZERO,
$ RWORK( L ), M )
DO 80 J = 1, N
DO 70 I = 1, M
C( I, J ) = CMPLX( REAL( C( I, J ) ),
$ RWORK( L+( J-1 )*M+I-1 ) )
70 CONTINUE
80 CONTINUE
*
RETURN
*
* End of CLACRM
*
END
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