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Mise à jour de lapack vers la version 3.3.0.
1: SUBROUTINE ZLARZB( SIDE, TRANS, DIRECT, STOREV, M, N, K, L, V, 2: $ LDV, T, LDT, C, LDC, WORK, LDWORK ) 3: * 4: * -- LAPACK routine (version 3.2) -- 5: * -- LAPACK is a software package provided by Univ. of Tennessee, -- 6: * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- 7: * November 2006 8: * 9: * .. Scalar Arguments .. 10: CHARACTER DIRECT, SIDE, STOREV, TRANS 11: INTEGER K, L, LDC, LDT, LDV, LDWORK, M, N 12: * .. 13: * .. Array Arguments .. 14: COMPLEX*16 C( LDC, * ), T( LDT, * ), V( LDV, * ), 15: $ WORK( LDWORK, * ) 16: * .. 17: * 18: * Purpose 19: * ======= 20: * 21: * ZLARZB applies a complex block reflector H or its transpose H**H 22: * to a complex distributed M-by-N C from the left or the right. 23: * 24: * Currently, only STOREV = 'R' and DIRECT = 'B' are supported. 25: * 26: * Arguments 27: * ========= 28: * 29: * SIDE (input) CHARACTER*1 30: * = 'L': apply H or H' from the Left 31: * = 'R': apply H or H' from the Right 32: * 33: * TRANS (input) CHARACTER*1 34: * = 'N': apply H (No transpose) 35: * = 'C': apply H' (Conjugate transpose) 36: * 37: * DIRECT (input) CHARACTER*1 38: * Indicates how H is formed from a product of elementary 39: * reflectors 40: * = 'F': H = H(1) H(2) . . . H(k) (Forward, not supported yet) 41: * = 'B': H = H(k) . . . H(2) H(1) (Backward) 42: * 43: * STOREV (input) CHARACTER*1 44: * Indicates how the vectors which define the elementary 45: * reflectors are stored: 46: * = 'C': Columnwise (not supported yet) 47: * = 'R': Rowwise 48: * 49: * M (input) INTEGER 50: * The number of rows of the matrix C. 51: * 52: * N (input) INTEGER 53: * The number of columns of the matrix C. 54: * 55: * K (input) INTEGER 56: * The order of the matrix T (= the number of elementary 57: * reflectors whose product defines the block reflector). 58: * 59: * L (input) INTEGER 60: * The number of columns of the matrix V containing the 61: * meaningful part of the Householder reflectors. 62: * If SIDE = 'L', M >= L >= 0, if SIDE = 'R', N >= L >= 0. 63: * 64: * V (input) COMPLEX*16 array, dimension (LDV,NV). 65: * If STOREV = 'C', NV = K; if STOREV = 'R', NV = L. 66: * 67: * LDV (input) INTEGER 68: * The leading dimension of the array V. 69: * If STOREV = 'C', LDV >= L; if STOREV = 'R', LDV >= K. 70: * 71: * T (input) COMPLEX*16 array, dimension (LDT,K) 72: * The triangular K-by-K matrix T in the representation of the 73: * block reflector. 74: * 75: * LDT (input) INTEGER 76: * The leading dimension of the array T. LDT >= K. 77: * 78: * C (input/output) COMPLEX*16 array, dimension (LDC,N) 79: * On entry, the M-by-N matrix C. 80: * On exit, C is overwritten by H*C or H'*C or C*H or C*H'. 81: * 82: * LDC (input) INTEGER 83: * The leading dimension of the array C. LDC >= max(1,M). 84: * 85: * WORK (workspace) COMPLEX*16 array, dimension (LDWORK,K) 86: * 87: * LDWORK (input) INTEGER 88: * The leading dimension of the array WORK. 89: * If SIDE = 'L', LDWORK >= max(1,N); 90: * if SIDE = 'R', LDWORK >= max(1,M). 91: * 92: * Further Details 93: * =============== 94: * 95: * Based on contributions by 96: * A. Petitet, Computer Science Dept., Univ. of Tenn., Knoxville, USA 97: * 98: * ===================================================================== 99: * 100: * .. Parameters .. 101: COMPLEX*16 ONE 102: PARAMETER ( ONE = ( 1.0D+0, 0.0D+0 ) ) 103: * .. 104: * .. Local Scalars .. 105: CHARACTER TRANST 106: INTEGER I, INFO, J 107: * .. 108: * .. External Functions .. 109: LOGICAL LSAME 110: EXTERNAL LSAME 111: * .. 112: * .. External Subroutines .. 113: EXTERNAL XERBLA, ZCOPY, ZGEMM, ZLACGV, ZTRMM 114: * .. 115: * .. Executable Statements .. 116: * 117: * Quick return if possible 118: * 119: IF( M.LE.0 .OR. N.LE.0 ) 120: $ RETURN 121: * 122: * Check for currently supported options 123: * 124: INFO = 0 125: IF( .NOT.LSAME( DIRECT, 'B' ) ) THEN 126: INFO = -3 127: ELSE IF( .NOT.LSAME( STOREV, 'R' ) ) THEN 128: INFO = -4 129: END IF 130: IF( INFO.NE.0 ) THEN 131: CALL XERBLA( 'ZLARZB', -INFO ) 132: RETURN 133: END IF 134: * 135: IF( LSAME( TRANS, 'N' ) ) THEN 136: TRANST = 'C' 137: ELSE 138: TRANST = 'N' 139: END IF 140: * 141: IF( LSAME( SIDE, 'L' ) ) THEN 142: * 143: * Form H * C or H' * C 144: * 145: * W( 1:n, 1:k ) = conjg( C( 1:k, 1:n )' ) 146: * 147: DO 10 J = 1, K 148: CALL ZCOPY( N, C( J, 1 ), LDC, WORK( 1, J ), 1 ) 149: 10 CONTINUE 150: * 151: * W( 1:n, 1:k ) = W( 1:n, 1:k ) + ... 152: * conjg( C( m-l+1:m, 1:n )' ) * V( 1:k, 1:l )' 153: * 154: IF( L.GT.0 ) 155: $ CALL ZGEMM( 'Transpose', 'Conjugate transpose', N, K, L, 156: $ ONE, C( M-L+1, 1 ), LDC, V, LDV, ONE, WORK, 157: $ LDWORK ) 158: * 159: * W( 1:n, 1:k ) = W( 1:n, 1:k ) * T' or W( 1:m, 1:k ) * T 160: * 161: CALL ZTRMM( 'Right', 'Lower', TRANST, 'Non-unit', N, K, ONE, T, 162: $ LDT, WORK, LDWORK ) 163: * 164: * C( 1:k, 1:n ) = C( 1:k, 1:n ) - conjg( W( 1:n, 1:k )' ) 165: * 166: DO 30 J = 1, N 167: DO 20 I = 1, K 168: C( I, J ) = C( I, J ) - WORK( J, I ) 169: 20 CONTINUE 170: 30 CONTINUE 171: * 172: * C( m-l+1:m, 1:n ) = C( m-l+1:m, 1:n ) - ... 173: * conjg( V( 1:k, 1:l )' ) * conjg( W( 1:n, 1:k )' ) 174: * 175: IF( L.GT.0 ) 176: $ CALL ZGEMM( 'Transpose', 'Transpose', L, N, K, -ONE, V, LDV, 177: $ WORK, LDWORK, ONE, C( M-L+1, 1 ), LDC ) 178: * 179: ELSE IF( LSAME( SIDE, 'R' ) ) THEN 180: * 181: * Form C * H or C * H' 182: * 183: * W( 1:m, 1:k ) = C( 1:m, 1:k ) 184: * 185: DO 40 J = 1, K 186: CALL ZCOPY( M, C( 1, J ), 1, WORK( 1, J ), 1 ) 187: 40 CONTINUE 188: * 189: * W( 1:m, 1:k ) = W( 1:m, 1:k ) + ... 190: * C( 1:m, n-l+1:n ) * conjg( V( 1:k, 1:l )' ) 191: * 192: IF( L.GT.0 ) 193: $ CALL ZGEMM( 'No transpose', 'Transpose', M, K, L, ONE, 194: $ C( 1, N-L+1 ), LDC, V, LDV, ONE, WORK, LDWORK ) 195: * 196: * W( 1:m, 1:k ) = W( 1:m, 1:k ) * conjg( T ) or 197: * W( 1:m, 1:k ) * conjg( T' ) 198: * 199: DO 50 J = 1, K 200: CALL ZLACGV( K-J+1, T( J, J ), 1 ) 201: 50 CONTINUE 202: CALL ZTRMM( 'Right', 'Lower', TRANS, 'Non-unit', M, K, ONE, T, 203: $ LDT, WORK, LDWORK ) 204: DO 60 J = 1, K 205: CALL ZLACGV( K-J+1, T( J, J ), 1 ) 206: 60 CONTINUE 207: * 208: * C( 1:m, 1:k ) = C( 1:m, 1:k ) - W( 1:m, 1:k ) 209: * 210: DO 80 J = 1, K 211: DO 70 I = 1, M 212: C( I, J ) = C( I, J ) - WORK( I, J ) 213: 70 CONTINUE 214: 80 CONTINUE 215: * 216: * C( 1:m, n-l+1:n ) = C( 1:m, n-l+1:n ) - ... 217: * W( 1:m, 1:k ) * conjg( V( 1:k, 1:l ) ) 218: * 219: DO 90 J = 1, L 220: CALL ZLACGV( K, V( 1, J ), 1 ) 221: 90 CONTINUE 222: IF( L.GT.0 ) 223: $ CALL ZGEMM( 'No transpose', 'No transpose', M, L, K, -ONE, 224: $ WORK, LDWORK, V, LDV, ONE, C( 1, N-L+1 ), LDC ) 225: DO 100 J = 1, L 226: CALL ZLACGV( K, V( 1, J ), 1 ) 227: 100 CONTINUE 228: * 229: END IF 230: * 231: RETURN 232: * 233: * End of ZLARZB 234: * 235: END