SUBROUTINE SMMCADD( M, N, ALPHA, A, LDA, BETA, B, LDB ) * * -- PBLAS auxiliary routine (version 2.0) -- * University of Tennessee, Knoxville, Oak Ridge National Laboratory, * and University of California, Berkeley. * April 1, 1998 * * .. Scalar Arguments .. INTEGER LDA, LDB, M, N REAL ALPHA, BETA * .. * .. Array Arguments .. REAL A( LDA, * ), B( LDB, * ) * .. * * Purpose * ======= * * SMMCADD performs the following operation: * * B := alpha * A + beta * B, * * where alpha, beta are scalars and A and B are m by n matrices. * * Arguments * ========= * * M (local input) INTEGER * On entry, M specifies the number of rows of A and B. M must * be at least zero. * * N (local input) INTEGER * On entry, N specifies the number of columns of A and B. * N must be at least zero. * * ALPHA (local input) REAL * On entry, ALPHA specifies the scalar alpha. When ALPHA is * supplied as zero then the local entries of the array A need * not be set on input. * * A (local input) REAL array * On entry, A is an array of dimension ( LDA, N ). * * LDA (local input) INTEGER * On entry, LDA specifies the leading dimension of the array A. * LDA must be at least max( 1, M ). * * BETA (local input) REAL * On entry, BETA specifies the scalar beta. When BETA is sup- * plied as zero then the local entries of the array B need not * be set on input. * * B (local input/local output) REAL array * On entry, B is an array of dimension ( LDB, N ). On exit, the * leading m by n part of A has been added to the leading m by n * part of B. * * LDB (local input) INTEGER * On entry, LDB specifies the leading dimension of the array B. * LDB must be at least max( 1, M ). * * -- Written on April 1, 1998 by * Antoine Petitet, University of Tennessee, Knoxville 37996, USA. * * ===================================================================== * * .. Parameters .. REAL ONE, ZERO PARAMETER ( ONE = 1.0E+0, ZERO = 0.0E+0 ) * .. * .. Local Scalars .. INTEGER I, J * .. * .. External Subroutines .. EXTERNAL SAXPY, SCOPY, SSCAL * .. * .. Executable Statements .. * IF( ALPHA.EQ.ONE ) THEN IF( BETA.EQ.ZERO ) THEN DO 20 J = 1, N CALL SCOPY( M, A( 1, J ), 1, B( 1, J ), 1 ) * DO 10 I = 1, M * B( I, J ) = A( I, J ) * 10 CONTINUE 20 CONTINUE ELSE IF( BETA.NE.ONE ) THEN DO 40 J = 1, N DO 30 I = 1, M B( I, J ) = A( I, J ) + BETA * B( I, J ) 30 CONTINUE 40 CONTINUE ELSE DO 60 J = 1, N CALL SAXPY( M, ONE, A( 1, J ), 1, B( 1, J ), 1 ) * DO 50 I = 1, M * B( I, J ) = A( I, J ) + B( I, J ) * 50 CONTINUE 60 CONTINUE END IF ELSE IF( ALPHA.NE.ZERO ) THEN IF( BETA.EQ.ZERO ) THEN DO 80 J = 1, N DO 70 I = 1, M B( I, J ) = ALPHA * A( I, J ) 70 CONTINUE 80 CONTINUE ELSE IF( BETA.NE.ONE ) THEN DO 100 J = 1, N DO 90 I = 1, M B( I, J ) = ALPHA * A( I, J ) + BETA * B( I, J ) 90 CONTINUE 100 CONTINUE ELSE DO 120 J = 1, N CALL SAXPY( M, ALPHA, A( 1, J ), 1, B( 1, J ), 1 ) * DO 110 I = 1, M * B( I, J ) = ALPHA * A( I, J ) + B( I, J ) * 110 CONTINUE 120 CONTINUE END IF ELSE IF( BETA.EQ.ZERO ) THEN DO 140 J = 1, N DO 130 I = 1, M B( I, J ) = ZERO 130 CONTINUE 140 CONTINUE ELSE IF( BETA.NE.ONE ) THEN DO 160 J = 1, N CALL SSCAL( M, BETA, B( 1, J ), 1 ) * DO 150 I = 1, M * B( I, J ) = BETA * B( I, J ) * 150 CONTINUE 160 CONTINUE END IF END IF * RETURN * * End of SMMCADD * END