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Diffstat (limited to 'src/lib/blas/dsbmv.f')
| -rw-r--r-- | src/lib/blas/dsbmv.f | 303 |
1 files changed, 0 insertions, 303 deletions
diff --git a/src/lib/blas/dsbmv.f b/src/lib/blas/dsbmv.f deleted file mode 100644 index 272042af..00000000 --- a/src/lib/blas/dsbmv.f +++ /dev/null @@ -1,303 +0,0 @@ - SUBROUTINE DSBMV ( UPLO, N, K, ALPHA, A, LDA, X, INCX, - $ BETA, Y, INCY ) -* .. Scalar Arguments .. - DOUBLE PRECISION ALPHA, BETA - INTEGER INCX, INCY, K, LDA, N - CHARACTER*1 UPLO -* .. Array Arguments .. - DOUBLE PRECISION A( LDA, * ), X( * ), Y( * ) -* .. -* -* Purpose -* ======= -* -* DSBMV performs the matrix-vector operation -* -* y := alpha*A*x + beta*y, -* -* where alpha and beta are scalars, x and y are n element vectors and -* A is an n by n symmetric band matrix, with k super-diagonals. -* -* Parameters -* ========== -* -* UPLO - CHARACTER*1. -* On entry, UPLO specifies whether the upper or lower -* triangular part of the band matrix A is being supplied as -* follows: -* -* UPLO = 'U' or 'u' The upper triangular part of A is -* being supplied. -* -* UPLO = 'L' or 'l' The lower triangular part of A is -* being supplied. -* -* Unchanged on exit. -* -* N - INTEGER. -* On entry, N specifies the order of the matrix A. -* N must be at least zero. -* Unchanged on exit. -* -* K - INTEGER. -* On entry, K specifies the number of super-diagonals of the -* matrix A. K must satisfy 0 .le. K. -* Unchanged on exit. -* -* ALPHA - DOUBLE PRECISION. -* On entry, ALPHA specifies the scalar alpha. -* Unchanged on exit. -* -* A - DOUBLE PRECISION array of DIMENSION ( LDA, n ). -* Before entry with UPLO = 'U' or 'u', the leading ( k + 1 ) -* by n part of the array A must contain the upper triangular -* band part of the symmetric matrix, supplied column by -* column, with the leading diagonal of the matrix in row -* ( k + 1 ) of the array, the first super-diagonal starting at -* position 2 in row k, and so on. The top left k by k triangle -* of the array A is not referenced. -* The following program segment will transfer the upper -* triangular part of a symmetric band matrix from conventional -* full matrix storage to band storage: -* -* DO 20, J = 1, N -* M = K + 1 - J -* DO 10, I = MAX( 1, J - K ), J -* A( M + I, J ) = matrix( I, J ) -* 10 CONTINUE -* 20 CONTINUE -* -* Before entry with UPLO = 'L' or 'l', the leading ( k + 1 ) -* by n part of the array A must contain the lower triangular -* band part of the symmetric matrix, supplied column by -* column, with the leading diagonal of the matrix in row 1 of -* the array, the first sub-diagonal starting at position 1 in -* row 2, and so on. The bottom right k by k triangle of the -* array A is not referenced. -* The following program segment will transfer the lower -* triangular part of a symmetric band matrix from conventional -* full matrix storage to band storage: -* -* DO 20, J = 1, N -* M = 1 - J -* DO 10, I = J, MIN( N, J + K ) -* A( M + I, J ) = matrix( I, J ) -* 10 CONTINUE -* 20 CONTINUE -* -* Unchanged on exit. -* -* LDA - INTEGER. -* On entry, LDA specifies the first dimension of A as declared -* in the calling (sub) program. LDA must be at least -* ( k + 1 ). -* Unchanged on exit. -* -* X - DOUBLE PRECISION array of DIMENSION at least -* ( 1 + ( n - 1 )*abs( INCX ) ). -* Before entry, the incremented array X must contain the -* vector x. -* Unchanged on exit. -* -* INCX - INTEGER. -* On entry, INCX specifies the increment for the elements of -* X. INCX must not be zero. -* Unchanged on exit. -* -* BETA - DOUBLE PRECISION. -* On entry, BETA specifies the scalar beta. -* Unchanged on exit. -* -* Y - DOUBLE PRECISION array of DIMENSION at least -* ( 1 + ( n - 1 )*abs( INCY ) ). -* Before entry, the incremented array Y must contain the -* vector y. On exit, Y is overwritten by the updated vector y. -* -* INCY - INTEGER. -* On entry, INCY specifies the increment for the elements of -* Y. INCY must not be zero. -* Unchanged on exit. -* -* -* Level 2 Blas routine. -* -* -- Written on 22-October-1986. -* Jack Dongarra, Argonne National Lab. -* Jeremy Du Croz, Nag Central Office. -* Sven Hammarling, Nag Central Office. -* Richard Hanson, Sandia National Labs. -* -* -* .. Parameters .. - DOUBLE PRECISION ONE , ZERO - PARAMETER ( ONE = 1.0D+0, ZERO = 0.0D+0 ) -* .. Local Scalars .. - DOUBLE PRECISION TEMP1, TEMP2 - INTEGER I, INFO, IX, IY, J, JX, JY, KPLUS1, KX, KY, L -* .. External Functions .. - LOGICAL LSAME - EXTERNAL LSAME -* .. External Subroutines .. - EXTERNAL XERBLA -* .. Intrinsic Functions .. - INTRINSIC MAX, MIN -* .. -* .. Executable Statements .. -* -* Test the input parameters. -* - INFO = 0 - IF ( .NOT.LSAME( UPLO, 'U' ).AND. - $ .NOT.LSAME( UPLO, 'L' ) )THEN - INFO = 1 - ELSE IF( N.LT.0 )THEN - INFO = 2 - ELSE IF( K.LT.0 )THEN - INFO = 3 - ELSE IF( LDA.LT.( K + 1 ) )THEN - INFO = 6 - ELSE IF( INCX.EQ.0 )THEN - INFO = 8 - ELSE IF( INCY.EQ.0 )THEN - INFO = 11 - END IF - IF( INFO.NE.0 )THEN - CALL XERBLA( 'DSBMV ', INFO ) - RETURN - END IF -* -* Quick return if possible. -* - IF( ( N.EQ.0 ).OR.( ( ALPHA.EQ.ZERO ).AND.( BETA.EQ.ONE ) ) ) - $ RETURN -* -* Set up the start points in X and Y. -* - IF( INCX.GT.0 )THEN - KX = 1 - ELSE - KX = 1 - ( N - 1 )*INCX - END IF - IF( INCY.GT.0 )THEN - KY = 1 - ELSE - KY = 1 - ( N - 1 )*INCY - END IF -* -* Start the operations. In this version the elements of the array A -* are accessed sequentially with one pass through A. -* -* First form y := beta*y. -* - IF( BETA.NE.ONE )THEN - IF( INCY.EQ.1 )THEN - IF( BETA.EQ.ZERO )THEN - DO 10, I = 1, N - Y( I ) = ZERO - 10 CONTINUE - ELSE - DO 20, I = 1, N - Y( I ) = BETA*Y( I ) - 20 CONTINUE - END IF - ELSE - IY = KY - IF( BETA.EQ.ZERO )THEN - DO 30, I = 1, N - Y( IY ) = ZERO - IY = IY + INCY - 30 CONTINUE - ELSE - DO 40, I = 1, N - Y( IY ) = BETA*Y( IY ) - IY = IY + INCY - 40 CONTINUE - END IF - END IF - END IF - IF( ALPHA.EQ.ZERO ) - $ RETURN - IF( LSAME( UPLO, 'U' ) )THEN -* -* Form y when upper triangle of A is stored. -* - KPLUS1 = K + 1 - IF( ( INCX.EQ.1 ).AND.( INCY.EQ.1 ) )THEN - DO 60, J = 1, N - TEMP1 = ALPHA*X( J ) - TEMP2 = ZERO - L = KPLUS1 - J - DO 50, I = MAX( 1, J - K ), J - 1 - Y( I ) = Y( I ) + TEMP1*A( L + I, J ) - TEMP2 = TEMP2 + A( L + I, J )*X( I ) - 50 CONTINUE - Y( J ) = Y( J ) + TEMP1*A( KPLUS1, J ) + ALPHA*TEMP2 - 60 CONTINUE - ELSE - JX = KX - JY = KY - DO 80, J = 1, N - TEMP1 = ALPHA*X( JX ) - TEMP2 = ZERO - IX = KX - IY = KY - L = KPLUS1 - J - DO 70, I = MAX( 1, J - K ), J - 1 - Y( IY ) = Y( IY ) + TEMP1*A( L + I, J ) - TEMP2 = TEMP2 + A( L + I, J )*X( IX ) - IX = IX + INCX - IY = IY + INCY - 70 CONTINUE - Y( JY ) = Y( JY ) + TEMP1*A( KPLUS1, J ) + ALPHA*TEMP2 - JX = JX + INCX - JY = JY + INCY - IF( J.GT.K )THEN - KX = KX + INCX - KY = KY + INCY - END IF - 80 CONTINUE - END IF - ELSE -* -* Form y when lower triangle of A is stored. -* - IF( ( INCX.EQ.1 ).AND.( INCY.EQ.1 ) )THEN - DO 100, J = 1, N - TEMP1 = ALPHA*X( J ) - TEMP2 = ZERO - Y( J ) = Y( J ) + TEMP1*A( 1, J ) - L = 1 - J - DO 90, I = J + 1, MIN( N, J + K ) - Y( I ) = Y( I ) + TEMP1*A( L + I, J ) - TEMP2 = TEMP2 + A( L + I, J )*X( I ) - 90 CONTINUE - Y( J ) = Y( J ) + ALPHA*TEMP2 - 100 CONTINUE - ELSE - JX = KX - JY = KY - DO 120, J = 1, N - TEMP1 = ALPHA*X( JX ) - TEMP2 = ZERO - Y( JY ) = Y( JY ) + TEMP1*A( 1, J ) - L = 1 - J - IX = JX - IY = JY - DO 110, I = J + 1, MIN( N, J + K ) - IX = IX + INCX - IY = IY + INCY - Y( IY ) = Y( IY ) + TEMP1*A( L + I, J ) - TEMP2 = TEMP2 + A( L + I, J )*X( IX ) - 110 CONTINUE - Y( JY ) = Y( JY ) + ALPHA*TEMP2 - JX = JX + INCX - JY = JY + INCY - 120 CONTINUE - END IF - END IF -* - RETURN -* -* End of DSBMV . -* - END |