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* ..* .. External Functions .. LOGICAL LSAME DOUBLE PRECISION DLAMCH EXTERNAL LSAME, DLAMCH* ..* .. Intrinsic Functions .. INTRINSIC ABS, MAX, MIN* ..* .. External Subroutines .. EXTERNAL XERBLA* ..* .. Executable Statements ..** Test the input arguments* INFO = 0* IF( LSAME( TYPE, 'G' ) ) THEN ITYPE = 0 ELSE IF( LSAME( TYPE, 'L' ) ) THEN ITYPE = 1 ELSE IF( LSAME( TYPE, 'U' ) ) THEN ITYPE = 2 ELSE IF( LSAME( TYPE, 'H' ) ) THEN ITYPE = 3 ELSE IF( LSAME( TYPE, 'B' ) ) THEN ITYPE = 4 ELSE IF( LSAME( TYPE, 'Q' ) ) THEN ITYPE = 5 ELSE IF( LSAME( TYPE, 'Z' ) ) THEN ITYPE = 6 ELSE ITYPE = -1 END IF* IF( ITYPE.EQ.-1 ) THEN INFO = -1 ELSE IF( CFROM.EQ.ZERO ) THEN INFO = -4 ELSE IF( M.LT.0 ) THEN INFO = -6 ELSE IF( N.LT.0 .OR. ( ITYPE.EQ.4 .AND. N.NE.M ) .OR. $ ( ITYPE.EQ.5 .AND. N.NE.M ) ) THEN INFO = -7 ELSE IF( ITYPE.LE.3 .AND. LDA.LT.MAX( 1, M ) ) THEN INFO = -9 ELSE IF( ITYPE.GE.4 ) THEN IF( KL.LT.0 .OR. KL.GT.MAX( M-1, 0 ) ) THEN INFO = -2 ELSE IF( KU.LT.0 .OR. KU.GT.MAX( N-1, 0 ) .OR. $ ( ( ITYPE.EQ.4 .OR. ITYPE.EQ.5 ) .AND. KL.NE.KU ) ) $ THEN INFO = -3 ELSE IF( ( ITYPE.EQ.4 .AND. LDA.LT.KL+1 ) .OR. $ ( ITYPE.EQ.5 .AND. LDA.LT.KU+1 ) .OR. $ ( ITYPE.EQ.6 .AND. LDA.LT.2*KL+KU+1 ) ) THEN INFO = -9 END IF END IF* IF( INFO.NE.0 ) THEN CALL XERBLA( 'DLASCL', -INFO ) RETURN END IF** Quick return if possible* IF( N.EQ.0 .OR. M.EQ.0 ) $ RETURN** Get machine parameters* SMLNUM = DLAMCH( 'S' ) BIGNUM = ONE / SMLNUM* CFROMC = CFROM CTOC = CTO* 10 CONTINUE CFROM1 = CFROMC*SMLNUM CTO1 = CTOC / BIGNUM IF( ABS( CFROM1 ).GT.ABS( CTOC ) .AND. CTOC.NE.ZERO ) THEN MUL = SMLNUM DONE = .FALSE. CFROMC = CFROM1 ELSE IF( ABS( CTO1 ).GT.ABS( CFROMC ) ) THEN MUL = BIGNUM DONE = .FALSE. CTOC = CTO1 ELSE MUL = CTOC / CFROMC DONE = .TRUE. END IF* IF( ITYPE.EQ.0 ) THEN** Full matrix* DO 30 J = 1, N DO 20 I = 1, M A( I, J ) = A( I, J )*MUL 20 CONTINUE 30 CONTINUE* ELSE IF( ITYPE.EQ.1 ) THEN** Lower triangular matrix* DO 50 J = 1, N DO 40 I = J, M A( I, J ) = A( I, J )*MUL 40 CONTINUE 50 CONTINUE* ELSE IF( ITYPE.EQ.2 ) THEN** Upper triangular matrix* DO 70 J = 1, N DO 60 I = 1, MIN( J, M ) A( I, J ) = A( I, J )*MUL 60 CONTINUE 70 CONTINUE* ELSE IF( ITYPE.EQ.3 ) THEN** Upper Hessenberg matrix* DO 90 J = 1, N DO 80 I = 1, MIN( J+1, M ) A( I, J ) = A( I, J )*MUL 80 CONTINUE 90 CONTINUE* ELSE IF( ITYPE.EQ.4 ) THEN** Lower half of a symmetric band matrix* K3 = KL + 1 K4 = N + 1 DO 110 J = 1, N DO 100 I = 1, MIN( K3, K4-J ) A( I, J ) = A( I, J )*MUL 100 CONTINUE 110 CONTINUE* ELSE IF( ITYPE.EQ.5 ) THEN** Upper half of a symmetric band matrix* K1 = KU + 2 K3 = KU + 1 DO 130 J = 1, N DO 120 I = MAX( K1-J, 1 ), K3 A( I, J ) = A( I, J )*MUL 120 CONTINUE 130 CONTINUE* ELSE IF( ITYPE.EQ.6 ) THEN** Band matrix* K1 = KL + KU + 2 K2 = KL + 1 K3 = 2*KL + KU + 1 K4 = KL + KU + 1 + M DO 150 J = 1, N DO 140 I = MAX( K1-J, K2 ), MIN( K3, K4-J ) A( I, J ) = A( I, J )*MUL 140 CONTINUE 150 CONTINUE* END IF* IF( .NOT.DONE ) $ GO TO 10* RETURN** End of DLASCL* END SUBROUTINE DLASET( UPLO, M, N, ALPHA, BETA, A, LDA )** -- LAPACK auxiliary routine (version 2.0) --* Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,* Courant Institute, Argonne National Lab, and Rice University* October 31, 1992** .. Scalar Arguments .. CHARACTER UPLO INTEGER LDA, M, N DOUBLE PRECISION ALPHA, BETA* ..* .. Array Arguments .. DOUBLE PRECISION A( LDA, * )* ..** Purpose* =======** DLASET initializes an m-by-n matrix A to BETA on the diagonal and* ALPHA on the offdiagonals.** Arguments* =========** UPLO (input) CHARACTER*1* Specifies the part of the matrix A to be set.* = 'U': Upper triangular part is set; the strictly lower* triangular part of A is not changed.* = 'L': Lower triangular part is set; the strictly upper* triangular part of A is not changed.* Otherwise: All of the matrix A is set.** M (input) INTEGER* The number of rows of the matrix A. M >= 0.** N (input) INTEGER* The number of columns of the matrix A. N >= 0.** ALPHA (input) DOUBLE PRECISION* The constant to which the offdiagonal elements are to be set.** BETA (input) DOUBLE PRECISION* The constant to which the diagonal elements are to be set.** A (input/output) DOUBLE PRECISION array, dimension (LDA,N)* On exit, the leading m-by-n submatrix of A is set as follows:** if UPLO = 'U', A(i,j) = ALPHA, 1<=i<=j-1, 1<=j<=n,* if UPLO = 'L', A(i,j) = ALPHA, j+1<=i<=m, 1<=j<=n,* otherwise, A(i,j) = ALPHA, 1<=i<=m, 1<=j<=n, i.ne.j,** and, for all UPLO, A(i,i) = BETA, 1<=i<=min(m,n).** LDA (input) INTEGER* The leading dimension of the array A. LDA >= max(1,M).** =====================================================================** .. Local Scalars .. INTEGER I, J* ..* .. External Functions .. LOGICAL LSAME EXTERNAL LSAME* ..* .. Intrinsic Functions .. INTRINSIC MIN* ..* .. Executable Statements ..* IF( LSAME( UPLO, 'U' ) ) THEN** Set the strictly upper triangular or trapezoidal part of the* array to ALPHA.* DO 20 J = 2, N DO 10 I = 1, MIN( J-1, M ) A( I, J ) = ALPHA 10 CONTINUE 20 CONTINUE* ELSE IF( LSAME( UPLO, 'L' ) ) THEN** Set the strictly lower triangular or trapezoidal part of the* array to ALPHA.* DO 40 J = 1, MIN( M, N ) DO 30 I = J + 1, M A( I, J ) = ALPHA 30 CONTINUE 40 CONTINUE* ELSE** Set the leading m-by-n submatrix to ALPHA.* DO 60 J = 1, N DO 50 I = 1, M A( I, J ) = ALPHA 50 CONTINUE 60 CONTINUE END IF** Set the first min(M,N) diagonal elements to BETA.* DO 70 I = 1, MIN( M, N ) A( I, I ) = BETA 70 CONTINUE* RETURN** End of DLASET* END SUBROUTINE DLASR( SIDE, PIVOT, DIRECT, M, N, C, S, A, LDA )** -- LAPACK auxiliary routine (version 2.0) --* Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,* Courant Institute, Argonne National Lab, and Rice University* October 31, 1992** .. Scalar Arguments .. CHARACTER DIRECT, PIVOT, SIDE INTEGER LDA, M, N* ..* .. Array Arguments .. DOUBLE PRECISION A( LDA, * ), C( * ), S( * )* ..** Purpose* =======** DLASR performs the transformation** A := P*A, when SIDE = 'L' or 'l' ( Left-hand side )** A := A*P', when SIDE = 'R' or 'r' ( Right-hand side )** where A is an m by n real matrix and P is an orthogonal matrix,* consisting of a sequence of plane rotations determined by the* parameters PIVOT and DIRECT as follows ( z = m when SIDE = 'L' or 'l'* and z = n when SIDE = 'R' or 'r' ):** When DIRECT = 'F' or 'f' ( Forward sequence ) then** P = P( z - 1 )*...*P( 2 )*P( 1 ),** and when DIRECT = 'B' or 'b' ( Backward sequence ) then** P = P( 1 )*P( 2 )*...*P( z - 1 ),** where P( k ) is a plane rotation matrix for the following planes:** when PIVOT = 'V' or 'v' ( Variable pivot ),* the plane ( k, k + 1 )** when PIVOT = 'T' or 't' ( Top pivot ),* the plane ( 1, k + 1 )** when PIVOT = 'B' or 'b' ( Bottom pivot ),* the plane ( k, z )** c( k ) and s( k ) must contain the cosine and sine that define the* matrix P( k ). The two by two plane rotation part of the matrix* P( k ), R( k ), is assumed to be of the form** R( k ) = ( c( k ) s( k ) ).* ( -s( k ) c( k ) )** This version vectorises across rows of the array A when SIDE = 'L'.** Arguments* =========** SIDE (input) CHARACTER*1* Specifies whether the plane rotation matrix P is applied to* A on the left or the right.* = 'L': Left, compute A := P*A* = 'R': Right, compute A:= A*P'** DIRECT (input) CHARACTER*1* Specifies whether P is a forward or backward sequence of* plane rotations.* = 'F': Forward, P = P( z - 1 )*...*P( 2 )*P( 1 )* = 'B': Backward, P = P( 1 )*P( 2 )*...*P( z - 1 )** PIVOT (input) CHARACTER*1* Specifies the plane for which P(k) is a plane rotation* matrix.* = 'V': Variable pivot, the plane (k,k+1)* = 'T': Top pivot, the plane (1,k+1)* = 'B': Bottom pivot, the plane (k,z)** M (input) INTEGER* The number of rows of the matrix A. If m <= 1, an immediate* return is effected.** N (input) INTEGER* The number of columns of the matrix A. If n <= 1, an* immediate return is effected.** C, S (input) DOUBLE PRECISION arrays, dimension* (M-1) if SIDE = 'L'* (N-1) if SIDE = 'R'* c(k) and s(k) contain the cosine and sine that define the* matrix P(k). The two by two plane rotation part of the* matrix P(k), R(k), is assumed to be of the form* R( k ) = ( c( k ) s( k ) ).* ( -s( k ) c( k ) )** A (input/output) DOUBLE PRECISION array, dimension (LDA,N)* The m by n matrix A. On exit, A is overwritten by P*A if* SIDE = 'R' or by A*P' if SIDE = 'L'.** LDA (input) INTEGER* The leading dimension of the array A. LDA >= max(1,M).** =====================================================================** .. Parameters .. DOUBLE PRECISION ONE, ZERO PARAMETER ( ONE = 1.0D+0, ZERO = 0.0D+0 )* ..* .. Local Scalars .. INTEGER I, INFO, J DOUBLE PRECISION CTEMP, STEMP, TEMP* ..* .. External Functions .. LOGICAL LSAME EXTERNAL LSAME* ..* .. External Subroutines .. EXTERNAL XERBLA* ..* .. Intrinsic Functions .. INTRINSIC MAX* ..* .. Executable Statements ..** Test the input parameters* INFO = 0 IF( .NOT.( LSAME( SIDE, 'L' ) .OR. LSAME( SIDE, 'R' ) ) ) THEN INFO = 1 ELSE IF( .NOT.( LSAME( PIVOT, 'V' ) .OR. LSAME( PIVOT, $ 'T' ) .OR. LSAME( PIVOT, 'B' ) ) ) THEN INFO = 2 ELSE IF( .NOT.( LSAME( DIRECT, 'F' ) .OR. LSAME( DIRECT, 'B' ) ) ) $ THEN INFO = 3 ELSE IF( M.LT.0 ) THEN INFO = 4 ELSE IF( N.LT.0 ) THEN INFO = 5 ELSE IF( LDA.LT.MAX( 1, M ) ) THEN INFO = 9 END IF IF( INFO.NE.0 ) THEN CALL XERBLA( 'DLASR ', INFO ) RETURN END IF** Quick return if possible* IF( ( M.EQ.0 ) .OR. ( N.EQ.0 ) ) $ RETURN IF( LSAME( SIDE, 'L' ) ) THEN*
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