| SUBROUTINE CHEMMF ( SIDE, UPLO, M, N, ALPHA, A, LDA, B, LDB, |
| $ BETA, C, LDC ) |
| * .. Scalar Arguments .. |
| CHARACTER*1 SIDE, UPLO |
| INTEGER M, N, LDA, LDB, LDC |
| COMPLEX ALPHA, BETA |
| * .. Array Arguments .. |
| COMPLEX A( LDA, * ), B( LDB, * ), C( LDC, * ) |
| * .. |
| * |
| * Purpose |
| * ======= |
| * |
| * CHEMM performs one of the matrix-matrix operations |
| * |
| * C := alpha*A*B + beta*C, |
| * |
| * or |
| * |
| * C := alpha*B*A + beta*C, |
| * |
| * where alpha and beta are scalars, A is an hermitian matrix and B and |
| * C are m by n matrices. |
| * |
| * Parameters |
| * ========== |
| * |
| * SIDE - CHARACTER*1. |
| * On entry, SIDE specifies whether the hermitian matrix A |
| * appears on the left or right in the operation as follows: |
| * |
| * SIDE = 'L' or 'l' C := alpha*A*B + beta*C, |
| * |
| * SIDE = 'R' or 'r' C := alpha*B*A + beta*C, |
| * |
| * Unchanged on exit. |
| * |
| * UPLO - CHARACTER*1. |
| * On entry, UPLO specifies whether the upper or lower |
| * triangular part of the hermitian matrix A is to be |
| * referenced as follows: |
| * |
| * UPLO = 'U' or 'u' Only the upper triangular part of the |
| * hermitian matrix is to be referenced. |
| * |
| * UPLO = 'L' or 'l' Only the lower triangular part of the |
| * hermitian matrix is to be referenced. |
| * |
| * Unchanged on exit. |
| * |
| * M - INTEGER. |
| * On entry, M specifies the number of rows of the matrix C. |
| * M must be at least zero. |
| * Unchanged on exit. |
| * |
| * N - INTEGER. |
| * On entry, N specifies the number of columns of the matrix C. |
| * N must be at least zero. |
| * Unchanged on exit. |
| * |
| * ALPHA - COMPLEX . |
| * On entry, ALPHA specifies the scalar alpha. |
| * Unchanged on exit. |
| * |
| * A - COMPLEX array of DIMENSION ( LDA, ka ), where ka is |
| * m when SIDE = 'L' or 'l' and is n otherwise. |
| * Before entry with SIDE = 'L' or 'l', the m by m part of |
| * the array A must contain the hermitian matrix, such that |
| * when UPLO = 'U' or 'u', the leading m by m upper triangular |
| * part of the array A must contain the upper triangular part |
| * of the hermitian matrix and the strictly lower triangular |
| * part of A is not referenced, and when UPLO = 'L' or 'l', |
| * the leading m by m lower triangular part of the array A |
| * must contain the lower triangular part of the hermitian |
| * matrix and the strictly upper triangular part of A is not |
| * referenced. |
| * Before entry with SIDE = 'R' or 'r', the n by n part of |
| * the array A must contain the hermitian matrix, such that |
| * when UPLO = 'U' or 'u', the leading n by n upper triangular |
| * part of the array A must contain the upper triangular part |
| * of the hermitian matrix and the strictly lower triangular |
| * part of A is not referenced, and when UPLO = 'L' or 'l', |
| * the leading n by n lower triangular part of the array A |
| * must contain the lower triangular part of the hermitian |
| * matrix and the strictly upper triangular part of A is not |
| * referenced. |
| * Note that the imaginary parts of the diagonal elements need |
| * not be set, they are assumed to be zero. |
| * Unchanged on exit. |
| * |
| * LDA - INTEGER. |
| * On entry, LDA specifies the first dimension of A as declared |
| * in the calling (sub) program. When SIDE = 'L' or 'l' then |
| * LDA must be at least max( 1, m ), otherwise LDA must be at |
| * least max( 1, n ). |
| * Unchanged on exit. |
| * |
| * B - COMPLEX array of DIMENSION ( LDB, n ). |
| * Before entry, the leading m by n part of the array B must |
| * contain the matrix B. |
| * Unchanged on exit. |
| * |
| * LDB - INTEGER. |
| * On entry, LDB specifies the first dimension of B as declared |
| * in the calling (sub) program. LDB must be at least |
| * max( 1, m ). |
| * Unchanged on exit. |
| * |
| * BETA - COMPLEX . |
| * On entry, BETA specifies the scalar beta. When BETA is |
| * supplied as zero then C need not be set on input. |
| * Unchanged on exit. |
| * |
| * C - COMPLEX array of DIMENSION ( LDC, n ). |
| * Before entry, the leading m by n part of the array C must |
| * contain the matrix C, except when beta is zero, in which |
| * case C need not be set on entry. |
| * On exit, the array C is overwritten by the m by n updated |
| * matrix. |
| * |
| * LDC - INTEGER. |
| * On entry, LDC specifies the first dimension of C as declared |
| * in the calling (sub) program. LDC must be at least |
| * max( 1, m ). |
| * Unchanged on exit. |
| * |
| * |
| * Level 3 Blas routine. |
| * |
| * -- Written on 8-February-1989. |
| * Jack Dongarra, Argonne National Laboratory. |
| * Iain Duff, AERE Harwell. |
| * Jeremy Du Croz, Numerical Algorithms Group Ltd. |
| * Sven Hammarling, Numerical Algorithms Group Ltd. |
| * |
| * |
| * .. External Functions .. |
| LOGICAL LSAME |
| EXTERNAL LSAME |
| * .. External Subroutines .. |
| EXTERNAL XERBLA |
| * .. Intrinsic Functions .. |
| INTRINSIC CONJG, MAX, REAL |
| * .. Local Scalars .. |
| LOGICAL UPPER |
| INTEGER I, INFO, J, K, NROWA |
| COMPLEX TEMP1, TEMP2 |
| * .. Parameters .. |
| COMPLEX ONE |
| PARAMETER ( ONE = ( 1.0E+0, 0.0E+0 ) ) |
| COMPLEX ZERO |
| PARAMETER ( ZERO = ( 0.0E+0, 0.0E+0 ) ) |
| * .. |
| * .. Executable Statements .. |
| * |
| * Set NROWA as the number of rows of A. |
| * |
| IF( LSAME( SIDE, 'L' ) )THEN |
| NROWA = M |
| ELSE |
| NROWA = N |
| END IF |
| UPPER = LSAME( UPLO, 'U' ) |
| * |
| * Test the input parameters. |
| * |
| INFO = 0 |
| IF( ( .NOT.LSAME( SIDE, 'L' ) ).AND. |
| $ ( .NOT.LSAME( SIDE, 'R' ) ) )THEN |
| INFO = 1 |
| ELSE IF( ( .NOT.UPPER ).AND. |
| $ ( .NOT.LSAME( UPLO, 'L' ) ) )THEN |
| INFO = 2 |
| ELSE IF( M .LT.0 )THEN |
| INFO = 3 |
| ELSE IF( N .LT.0 )THEN |
| INFO = 4 |
| ELSE IF( LDA.LT.MAX( 1, NROWA ) )THEN |
| INFO = 7 |
| ELSE IF( LDB.LT.MAX( 1, M ) )THEN |
| INFO = 9 |
| ELSE IF( LDC.LT.MAX( 1, M ) )THEN |
| INFO = 12 |
| END IF |
| IF( INFO.NE.0 )THEN |
| CALL XERBLA( 'CHEMM3M', INFO ) |
| RETURN |
| END IF |
| * |
| * Quick return if possible. |
| * |
| IF( ( M.EQ.0 ).OR.( N.EQ.0 ).OR. |
| $ ( ( ALPHA.EQ.ZERO ).AND.( BETA.EQ.ONE ) ) ) |
| $ RETURN |
| * |
| * And when alpha.eq.zero. |
| * |
| IF( ALPHA.EQ.ZERO )THEN |
| IF( BETA.EQ.ZERO )THEN |
| DO 20, J = 1, N |
| DO 10, I = 1, M |
| C( I, J ) = ZERO |
| 10 CONTINUE |
| 20 CONTINUE |
| ELSE |
| DO 40, J = 1, N |
| DO 30, I = 1, M |
| C( I, J ) = BETA*C( I, J ) |
| 30 CONTINUE |
| 40 CONTINUE |
| END IF |
| RETURN |
| END IF |
| * |
| * Start the operations. |
| * |
| IF( LSAME( SIDE, 'L' ) )THEN |
| * |
| * Form C := alpha*A*B + beta*C. |
| * |
| IF( UPPER )THEN |
| DO 70, J = 1, N |
| DO 60, I = 1, M |
| TEMP1 = ALPHA*B( I, J ) |
| TEMP2 = ZERO |
| DO 50, K = 1, I - 1 |
| C( K, J ) = C( K, J ) + TEMP1*A( K, I ) |
| TEMP2 = TEMP2 + |
| $ B( K, J )*CONJG( A( K, I ) ) |
| 50 CONTINUE |
| IF( BETA.EQ.ZERO )THEN |
| C( I, J ) = TEMP1*REAL( A( I, I ) ) + |
| $ ALPHA*TEMP2 |
| ELSE |
| C( I, J ) = BETA *C( I, J ) + |
| $ TEMP1*REAL( A( I, I ) ) + |
| $ ALPHA*TEMP2 |
| END IF |
| 60 CONTINUE |
| 70 CONTINUE |
| ELSE |
| DO 100, J = 1, N |
| DO 90, I = M, 1, -1 |
| TEMP1 = ALPHA*B( I, J ) |
| TEMP2 = ZERO |
| DO 80, K = I + 1, M |
| C( K, J ) = C( K, J ) + TEMP1*A( K, I ) |
| TEMP2 = TEMP2 + |
| $ B( K, J )*CONJG( A( K, I ) ) |
| 80 CONTINUE |
| IF( BETA.EQ.ZERO )THEN |
| C( I, J ) = TEMP1*REAL( A( I, I ) ) + |
| $ ALPHA*TEMP2 |
| ELSE |
| C( I, J ) = BETA *C( I, J ) + |
| $ TEMP1*REAL( A( I, I ) ) + |
| $ ALPHA*TEMP2 |
| END IF |
| 90 CONTINUE |
| 100 CONTINUE |
| END IF |
| ELSE |
| * |
| * Form C := alpha*B*A + beta*C. |
| * |
| DO 170, J = 1, N |
| TEMP1 = ALPHA*REAL( A( J, J ) ) |
| IF( BETA.EQ.ZERO )THEN |
| DO 110, I = 1, M |
| C( I, J ) = TEMP1*B( I, J ) |
| 110 CONTINUE |
| ELSE |
| DO 120, I = 1, M |
| C( I, J ) = BETA*C( I, J ) + TEMP1*B( I, J ) |
| 120 CONTINUE |
| END IF |
| DO 140, K = 1, J - 1 |
| IF( UPPER )THEN |
| TEMP1 = ALPHA*A( K, J ) |
| ELSE |
| TEMP1 = ALPHA*CONJG( A( J, K ) ) |
| END IF |
| DO 130, I = 1, M |
| C( I, J ) = C( I, J ) + TEMP1*B( I, K ) |
| 130 CONTINUE |
| 140 CONTINUE |
| DO 160, K = J + 1, N |
| IF( UPPER )THEN |
| TEMP1 = ALPHA*CONJG( A( J, K ) ) |
| ELSE |
| TEMP1 = ALPHA*A( K, J ) |
| END IF |
| DO 150, I = 1, M |
| C( I, J ) = C( I, J ) + TEMP1*B( I, K ) |
| 150 CONTINUE |
| 160 CONTINUE |
| 170 CONTINUE |
| END IF |
| * |
| RETURN |
| * |
| * End of CHEMM . |
| * |
| END |
