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Diffstat (limited to 'src/fortran/lapack/dlarfx.f')
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diff --git a/src/fortran/lapack/dlarfx.f b/src/fortran/lapack/dlarfx.f new file mode 100644 index 0000000..cc4654e --- /dev/null +++ b/src/fortran/lapack/dlarfx.f @@ -0,0 +1,638 @@ + SUBROUTINE DLARFX( SIDE, M, N, V, TAU, C, LDC, WORK ) +* +* -- LAPACK auxiliary routine (version 3.1) -- +* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. +* November 2006 +* +* .. Scalar Arguments .. + CHARACTER SIDE + INTEGER LDC, M, N + DOUBLE PRECISION TAU +* .. +* .. Array Arguments .. + DOUBLE PRECISION C( LDC, * ), V( * ), WORK( * ) +* .. +* +* Purpose +* ======= +* +* DLARFX applies a real elementary reflector H to a real m by n +* matrix C, from either the left or the right. H is represented in the +* form +* +* H = I - tau * v * v' +* +* where tau is a real scalar and v is a real vector. +* +* If tau = 0, then H is taken to be the unit matrix +* +* This version uses inline code if H has order < 11. +* +* Arguments +* ========= +* +* SIDE (input) CHARACTER*1 +* = 'L': form H * C +* = 'R': form C * H +* +* M (input) INTEGER +* The number of rows of the matrix C. +* +* N (input) INTEGER +* The number of columns of the matrix C. +* +* V (input) DOUBLE PRECISION array, dimension (M) if SIDE = 'L' +* or (N) if SIDE = 'R' +* The vector v in the representation of H. +* +* TAU (input) DOUBLE PRECISION +* The value tau in the representation of H. +* +* C (input/output) DOUBLE PRECISION array, dimension (LDC,N) +* On entry, the m by n matrix C. +* On exit, C is overwritten by the matrix H * C if SIDE = 'L', +* or C * H if SIDE = 'R'. +* +* LDC (input) INTEGER +* The leading dimension of the array C. LDA >= (1,M). +* +* WORK (workspace) DOUBLE PRECISION array, dimension +* (N) if SIDE = 'L' +* or (M) if SIDE = 'R' +* WORK is not referenced if H has order < 11. +* +* ===================================================================== +* +* .. Parameters .. + DOUBLE PRECISION ZERO, ONE + PARAMETER ( ZERO = 0.0D+0, ONE = 1.0D+0 ) +* .. +* .. Local Scalars .. + INTEGER J + DOUBLE PRECISION SUM, T1, T10, T2, T3, T4, T5, T6, T7, T8, T9, + $ V1, V10, V2, V3, V4, V5, V6, V7, V8, V9 +* .. +* .. External Functions .. + LOGICAL LSAME + EXTERNAL LSAME +* .. +* .. External Subroutines .. + EXTERNAL DGEMV, DGER +* .. +* .. Executable Statements .. +* + IF( TAU.EQ.ZERO ) + $ RETURN + IF( LSAME( SIDE, 'L' ) ) THEN +* +* Form H * C, where H has order m. +* + GO TO ( 10, 30, 50, 70, 90, 110, 130, 150, + $ 170, 190 )M +* +* Code for general M +* +* w := C'*v +* + CALL DGEMV( 'Transpose', M, N, ONE, C, LDC, V, 1, ZERO, WORK, + $ 1 ) +* +* C := C - tau * v * w' +* + CALL DGER( M, N, -TAU, V, 1, WORK, 1, C, LDC ) + GO TO 410 + 10 CONTINUE +* +* Special code for 1 x 1 Householder +* + T1 = ONE - TAU*V( 1 )*V( 1 ) + DO 20 J = 1, N + C( 1, J ) = T1*C( 1, J ) + 20 CONTINUE + GO TO 410 + 30 CONTINUE +* +* Special code for 2 x 2 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + DO 40 J = 1, N + SUM = V1*C( 1, J ) + V2*C( 2, J ) + C( 1, J ) = C( 1, J ) - SUM*T1 + C( 2, J ) = C( 2, J ) - SUM*T2 + 40 CONTINUE + GO TO 410 + 50 CONTINUE +* +* Special code for 3 x 3 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + V3 = V( 3 ) + T3 = TAU*V3 + DO 60 J = 1, N + SUM = V1*C( 1, J ) + V2*C( 2, J ) + V3*C( 3, J ) + C( 1, J ) = C( 1, J ) - SUM*T1 + C( 2, J ) = C( 2, J ) - SUM*T2 + C( 3, J ) = C( 3, J ) - SUM*T3 + 60 CONTINUE + GO TO 410 + 70 CONTINUE +* +* Special code for 4 x 4 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + V3 = V( 3 ) + T3 = TAU*V3 + V4 = V( 4 ) + T4 = TAU*V4 + DO 80 J = 1, N + SUM = V1*C( 1, J ) + V2*C( 2, J ) + V3*C( 3, J ) + + $ V4*C( 4, J ) + C( 1, J ) = C( 1, J ) - SUM*T1 + C( 2, J ) = C( 2, J ) - SUM*T2 + C( 3, J ) = C( 3, J ) - SUM*T3 + C( 4, J ) = C( 4, J ) - SUM*T4 + 80 CONTINUE + GO TO 410 + 90 CONTINUE +* +* Special code for 5 x 5 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + V3 = V( 3 ) + T3 = TAU*V3 + V4 = V( 4 ) + T4 = TAU*V4 + V5 = V( 5 ) + T5 = TAU*V5 + DO 100 J = 1, N + SUM = V1*C( 1, J ) + V2*C( 2, J ) + V3*C( 3, J ) + + $ V4*C( 4, J ) + V5*C( 5, J ) + C( 1, J ) = C( 1, J ) - SUM*T1 + C( 2, J ) = C( 2, J ) - SUM*T2 + C( 3, J ) = C( 3, J ) - SUM*T3 + C( 4, J ) = C( 4, J ) - SUM*T4 + C( 5, J ) = C( 5, J ) - SUM*T5 + 100 CONTINUE + GO TO 410 + 110 CONTINUE +* +* Special code for 6 x 6 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + V3 = V( 3 ) + T3 = TAU*V3 + V4 = V( 4 ) + T4 = TAU*V4 + V5 = V( 5 ) + T5 = TAU*V5 + V6 = V( 6 ) + T6 = TAU*V6 + DO 120 J = 1, N + SUM = V1*C( 1, J ) + V2*C( 2, J ) + V3*C( 3, J ) + + $ V4*C( 4, J ) + V5*C( 5, J ) + V6*C( 6, J ) + C( 1, J ) = C( 1, J ) - SUM*T1 + C( 2, J ) = C( 2, J ) - SUM*T2 + C( 3, J ) = C( 3, J ) - SUM*T3 + C( 4, J ) = C( 4, J ) - SUM*T4 + C( 5, J ) = C( 5, J ) - SUM*T5 + C( 6, J ) = C( 6, J ) - SUM*T6 + 120 CONTINUE + GO TO 410 + 130 CONTINUE +* +* Special code for 7 x 7 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + V3 = V( 3 ) + T3 = TAU*V3 + V4 = V( 4 ) + T4 = TAU*V4 + V5 = V( 5 ) + T5 = TAU*V5 + V6 = V( 6 ) + T6 = TAU*V6 + V7 = V( 7 ) + T7 = TAU*V7 + DO 140 J = 1, N + SUM = V1*C( 1, J ) + V2*C( 2, J ) + V3*C( 3, J ) + + $ V4*C( 4, J ) + V5*C( 5, J ) + V6*C( 6, J ) + + $ V7*C( 7, J ) + C( 1, J ) = C( 1, J ) - SUM*T1 + C( 2, J ) = C( 2, J ) - SUM*T2 + C( 3, J ) = C( 3, J ) - SUM*T3 + C( 4, J ) = C( 4, J ) - SUM*T4 + C( 5, J ) = C( 5, J ) - SUM*T5 + C( 6, J ) = C( 6, J ) - SUM*T6 + C( 7, J ) = C( 7, J ) - SUM*T7 + 140 CONTINUE + GO TO 410 + 150 CONTINUE +* +* Special code for 8 x 8 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + V3 = V( 3 ) + T3 = TAU*V3 + V4 = V( 4 ) + T4 = TAU*V4 + V5 = V( 5 ) + T5 = TAU*V5 + V6 = V( 6 ) + T6 = TAU*V6 + V7 = V( 7 ) + T7 = TAU*V7 + V8 = V( 8 ) + T8 = TAU*V8 + DO 160 J = 1, N + SUM = V1*C( 1, J ) + V2*C( 2, J ) + V3*C( 3, J ) + + $ V4*C( 4, J ) + V5*C( 5, J ) + V6*C( 6, J ) + + $ V7*C( 7, J ) + V8*C( 8, J ) + C( 1, J ) = C( 1, J ) - SUM*T1 + C( 2, J ) = C( 2, J ) - SUM*T2 + C( 3, J ) = C( 3, J ) - SUM*T3 + C( 4, J ) = C( 4, J ) - SUM*T4 + C( 5, J ) = C( 5, J ) - SUM*T5 + C( 6, J ) = C( 6, J ) - SUM*T6 + C( 7, J ) = C( 7, J ) - SUM*T7 + C( 8, J ) = C( 8, J ) - SUM*T8 + 160 CONTINUE + GO TO 410 + 170 CONTINUE +* +* Special code for 9 x 9 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + V3 = V( 3 ) + T3 = TAU*V3 + V4 = V( 4 ) + T4 = TAU*V4 + V5 = V( 5 ) + T5 = TAU*V5 + V6 = V( 6 ) + T6 = TAU*V6 + V7 = V( 7 ) + T7 = TAU*V7 + V8 = V( 8 ) + T8 = TAU*V8 + V9 = V( 9 ) + T9 = TAU*V9 + DO 180 J = 1, N + SUM = V1*C( 1, J ) + V2*C( 2, J ) + V3*C( 3, J ) + + $ V4*C( 4, J ) + V5*C( 5, J ) + V6*C( 6, J ) + + $ V7*C( 7, J ) + V8*C( 8, J ) + V9*C( 9, J ) + C( 1, J ) = C( 1, J ) - SUM*T1 + C( 2, J ) = C( 2, J ) - SUM*T2 + C( 3, J ) = C( 3, J ) - SUM*T3 + C( 4, J ) = C( 4, J ) - SUM*T4 + C( 5, J ) = C( 5, J ) - SUM*T5 + C( 6, J ) = C( 6, J ) - SUM*T6 + C( 7, J ) = C( 7, J ) - SUM*T7 + C( 8, J ) = C( 8, J ) - SUM*T8 + C( 9, J ) = C( 9, J ) - SUM*T9 + 180 CONTINUE + GO TO 410 + 190 CONTINUE +* +* Special code for 10 x 10 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + V3 = V( 3 ) + T3 = TAU*V3 + V4 = V( 4 ) + T4 = TAU*V4 + V5 = V( 5 ) + T5 = TAU*V5 + V6 = V( 6 ) + T6 = TAU*V6 + V7 = V( 7 ) + T7 = TAU*V7 + V8 = V( 8 ) + T8 = TAU*V8 + V9 = V( 9 ) + T9 = TAU*V9 + V10 = V( 10 ) + T10 = TAU*V10 + DO 200 J = 1, N + SUM = V1*C( 1, J ) + V2*C( 2, J ) + V3*C( 3, J ) + + $ V4*C( 4, J ) + V5*C( 5, J ) + V6*C( 6, J ) + + $ V7*C( 7, J ) + V8*C( 8, J ) + V9*C( 9, J ) + + $ V10*C( 10, J ) + C( 1, J ) = C( 1, J ) - SUM*T1 + C( 2, J ) = C( 2, J ) - SUM*T2 + C( 3, J ) = C( 3, J ) - SUM*T3 + C( 4, J ) = C( 4, J ) - SUM*T4 + C( 5, J ) = C( 5, J ) - SUM*T5 + C( 6, J ) = C( 6, J ) - SUM*T6 + C( 7, J ) = C( 7, J ) - SUM*T7 + C( 8, J ) = C( 8, J ) - SUM*T8 + C( 9, J ) = C( 9, J ) - SUM*T9 + C( 10, J ) = C( 10, J ) - SUM*T10 + 200 CONTINUE + GO TO 410 + ELSE +* +* Form C * H, where H has order n. +* + GO TO ( 210, 230, 250, 270, 290, 310, 330, 350, + $ 370, 390 )N +* +* Code for general N +* +* w := C * v +* + CALL DGEMV( 'No transpose', M, N, ONE, C, LDC, V, 1, ZERO, + $ WORK, 1 ) +* +* C := C - tau * w * v' +* + CALL DGER( M, N, -TAU, WORK, 1, V, 1, C, LDC ) + GO TO 410 + 210 CONTINUE +* +* Special code for 1 x 1 Householder +* + T1 = ONE - TAU*V( 1 )*V( 1 ) + DO 220 J = 1, M + C( J, 1 ) = T1*C( J, 1 ) + 220 CONTINUE + GO TO 410 + 230 CONTINUE +* +* Special code for 2 x 2 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + DO 240 J = 1, M + SUM = V1*C( J, 1 ) + V2*C( J, 2 ) + C( J, 1 ) = C( J, 1 ) - SUM*T1 + C( J, 2 ) = C( J, 2 ) - SUM*T2 + 240 CONTINUE + GO TO 410 + 250 CONTINUE +* +* Special code for 3 x 3 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + V3 = V( 3 ) + T3 = TAU*V3 + DO 260 J = 1, M + SUM = V1*C( J, 1 ) + V2*C( J, 2 ) + V3*C( J, 3 ) + C( J, 1 ) = C( J, 1 ) - SUM*T1 + C( J, 2 ) = C( J, 2 ) - SUM*T2 + C( J, 3 ) = C( J, 3 ) - SUM*T3 + 260 CONTINUE + GO TO 410 + 270 CONTINUE +* +* Special code for 4 x 4 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + V3 = V( 3 ) + T3 = TAU*V3 + V4 = V( 4 ) + T4 = TAU*V4 + DO 280 J = 1, M + SUM = V1*C( J, 1 ) + V2*C( J, 2 ) + V3*C( J, 3 ) + + $ V4*C( J, 4 ) + C( J, 1 ) = C( J, 1 ) - SUM*T1 + C( J, 2 ) = C( J, 2 ) - SUM*T2 + C( J, 3 ) = C( J, 3 ) - SUM*T3 + C( J, 4 ) = C( J, 4 ) - SUM*T4 + 280 CONTINUE + GO TO 410 + 290 CONTINUE +* +* Special code for 5 x 5 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + V3 = V( 3 ) + T3 = TAU*V3 + V4 = V( 4 ) + T4 = TAU*V4 + V5 = V( 5 ) + T5 = TAU*V5 + DO 300 J = 1, M + SUM = V1*C( J, 1 ) + V2*C( J, 2 ) + V3*C( J, 3 ) + + $ V4*C( J, 4 ) + V5*C( J, 5 ) + C( J, 1 ) = C( J, 1 ) - SUM*T1 + C( J, 2 ) = C( J, 2 ) - SUM*T2 + C( J, 3 ) = C( J, 3 ) - SUM*T3 + C( J, 4 ) = C( J, 4 ) - SUM*T4 + C( J, 5 ) = C( J, 5 ) - SUM*T5 + 300 CONTINUE + GO TO 410 + 310 CONTINUE +* +* Special code for 6 x 6 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + V3 = V( 3 ) + T3 = TAU*V3 + V4 = V( 4 ) + T4 = TAU*V4 + V5 = V( 5 ) + T5 = TAU*V5 + V6 = V( 6 ) + T6 = TAU*V6 + DO 320 J = 1, M + SUM = V1*C( J, 1 ) + V2*C( J, 2 ) + V3*C( J, 3 ) + + $ V4*C( J, 4 ) + V5*C( J, 5 ) + V6*C( J, 6 ) + C( J, 1 ) = C( J, 1 ) - SUM*T1 + C( J, 2 ) = C( J, 2 ) - SUM*T2 + C( J, 3 ) = C( J, 3 ) - SUM*T3 + C( J, 4 ) = C( J, 4 ) - SUM*T4 + C( J, 5 ) = C( J, 5 ) - SUM*T5 + C( J, 6 ) = C( J, 6 ) - SUM*T6 + 320 CONTINUE + GO TO 410 + 330 CONTINUE +* +* Special code for 7 x 7 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + V3 = V( 3 ) + T3 = TAU*V3 + V4 = V( 4 ) + T4 = TAU*V4 + V5 = V( 5 ) + T5 = TAU*V5 + V6 = V( 6 ) + T6 = TAU*V6 + V7 = V( 7 ) + T7 = TAU*V7 + DO 340 J = 1, M + SUM = V1*C( J, 1 ) + V2*C( J, 2 ) + V3*C( J, 3 ) + + $ V4*C( J, 4 ) + V5*C( J, 5 ) + V6*C( J, 6 ) + + $ V7*C( J, 7 ) + C( J, 1 ) = C( J, 1 ) - SUM*T1 + C( J, 2 ) = C( J, 2 ) - SUM*T2 + C( J, 3 ) = C( J, 3 ) - SUM*T3 + C( J, 4 ) = C( J, 4 ) - SUM*T4 + C( J, 5 ) = C( J, 5 ) - SUM*T5 + C( J, 6 ) = C( J, 6 ) - SUM*T6 + C( J, 7 ) = C( J, 7 ) - SUM*T7 + 340 CONTINUE + GO TO 410 + 350 CONTINUE +* +* Special code for 8 x 8 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + V3 = V( 3 ) + T3 = TAU*V3 + V4 = V( 4 ) + T4 = TAU*V4 + V5 = V( 5 ) + T5 = TAU*V5 + V6 = V( 6 ) + T6 = TAU*V6 + V7 = V( 7 ) + T7 = TAU*V7 + V8 = V( 8 ) + T8 = TAU*V8 + DO 360 J = 1, M + SUM = V1*C( J, 1 ) + V2*C( J, 2 ) + V3*C( J, 3 ) + + $ V4*C( J, 4 ) + V5*C( J, 5 ) + V6*C( J, 6 ) + + $ V7*C( J, 7 ) + V8*C( J, 8 ) + C( J, 1 ) = C( J, 1 ) - SUM*T1 + C( J, 2 ) = C( J, 2 ) - SUM*T2 + C( J, 3 ) = C( J, 3 ) - SUM*T3 + C( J, 4 ) = C( J, 4 ) - SUM*T4 + C( J, 5 ) = C( J, 5 ) - SUM*T5 + C( J, 6 ) = C( J, 6 ) - SUM*T6 + C( J, 7 ) = C( J, 7 ) - SUM*T7 + C( J, 8 ) = C( J, 8 ) - SUM*T8 + 360 CONTINUE + GO TO 410 + 370 CONTINUE +* +* Special code for 9 x 9 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + V3 = V( 3 ) + T3 = TAU*V3 + V4 = V( 4 ) + T4 = TAU*V4 + V5 = V( 5 ) + T5 = TAU*V5 + V6 = V( 6 ) + T6 = TAU*V6 + V7 = V( 7 ) + T7 = TAU*V7 + V8 = V( 8 ) + T8 = TAU*V8 + V9 = V( 9 ) + T9 = TAU*V9 + DO 380 J = 1, M + SUM = V1*C( J, 1 ) + V2*C( J, 2 ) + V3*C( J, 3 ) + + $ V4*C( J, 4 ) + V5*C( J, 5 ) + V6*C( J, 6 ) + + $ V7*C( J, 7 ) + V8*C( J, 8 ) + V9*C( J, 9 ) + C( J, 1 ) = C( J, 1 ) - SUM*T1 + C( J, 2 ) = C( J, 2 ) - SUM*T2 + C( J, 3 ) = C( J, 3 ) - SUM*T3 + C( J, 4 ) = C( J, 4 ) - SUM*T4 + C( J, 5 ) = C( J, 5 ) - SUM*T5 + C( J, 6 ) = C( J, 6 ) - SUM*T6 + C( J, 7 ) = C( J, 7 ) - SUM*T7 + C( J, 8 ) = C( J, 8 ) - SUM*T8 + C( J, 9 ) = C( J, 9 ) - SUM*T9 + 380 CONTINUE + GO TO 410 + 390 CONTINUE +* +* Special code for 10 x 10 Householder +* + V1 = V( 1 ) + T1 = TAU*V1 + V2 = V( 2 ) + T2 = TAU*V2 + V3 = V( 3 ) + T3 = TAU*V3 + V4 = V( 4 ) + T4 = TAU*V4 + V5 = V( 5 ) + T5 = TAU*V5 + V6 = V( 6 ) + T6 = TAU*V6 + V7 = V( 7 ) + T7 = TAU*V7 + V8 = V( 8 ) + T8 = TAU*V8 + V9 = V( 9 ) + T9 = TAU*V9 + V10 = V( 10 ) + T10 = TAU*V10 + DO 400 J = 1, M + SUM = V1*C( J, 1 ) + V2*C( J, 2 ) + V3*C( J, 3 ) + + $ V4*C( J, 4 ) + V5*C( J, 5 ) + V6*C( J, 6 ) + + $ V7*C( J, 7 ) + V8*C( J, 8 ) + V9*C( J, 9 ) + + $ V10*C( J, 10 ) + C( J, 1 ) = C( J, 1 ) - SUM*T1 + C( J, 2 ) = C( J, 2 ) - SUM*T2 + C( J, 3 ) = C( J, 3 ) - SUM*T3 + C( J, 4 ) = C( J, 4 ) - SUM*T4 + C( J, 5 ) = C( J, 5 ) - SUM*T5 + C( J, 6 ) = C( J, 6 ) - SUM*T6 + C( J, 7 ) = C( J, 7 ) - SUM*T7 + C( J, 8 ) = C( J, 8 ) - SUM*T8 + C( J, 9 ) = C( J, 9 ) - SUM*T9 + C( J, 10 ) = C( J, 10 ) - SUM*T10 + 400 CONTINUE + GO TO 410 + END IF + 410 CONTINUE + RETURN +* +* End of DLARFX +* + END |