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Diffstat (limited to 'blas/fortran/dsbmv.f')
| -rw-r--r-- | blas/fortran/dsbmv.f | 304 |
1 files changed, 0 insertions, 304 deletions
diff --git a/blas/fortran/dsbmv.f b/blas/fortran/dsbmv.f deleted file mode 100644 index 8c82d1fa1..000000000 --- a/blas/fortran/dsbmv.f +++ /dev/null @@ -1,304 +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 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. -* -* Arguments -* ========== -* -* 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 -* .. -* -* 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 |