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Mise à jour de lapack vers la version 3.3.0.
1: SUBROUTINE DORML2( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, 2: $ WORK, INFO ) 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 SIDE, TRANS 11: INTEGER INFO, K, LDA, LDC, M, N 12: * .. 13: * .. Array Arguments .. 14: DOUBLE PRECISION A( LDA, * ), C( LDC, * ), TAU( * ), WORK( * ) 15: * .. 16: * 17: * Purpose 18: * ======= 19: * 20: * DORML2 overwrites the general real m by n matrix C with 21: * 22: * Q * C if SIDE = 'L' and TRANS = 'N', or 23: * 24: * Q'* C if SIDE = 'L' and TRANS = 'T', or 25: * 26: * C * Q if SIDE = 'R' and TRANS = 'N', or 27: * 28: * C * Q' if SIDE = 'R' and TRANS = 'T', 29: * 30: * where Q is a real orthogonal matrix defined as the product of k 31: * elementary reflectors 32: * 33: * Q = H(k) . . . H(2) H(1) 34: * 35: * as returned by DGELQF. Q is of order m if SIDE = 'L' and of order n 36: * if SIDE = 'R'. 37: * 38: * Arguments 39: * ========= 40: * 41: * SIDE (input) CHARACTER*1 42: * = 'L': apply Q or Q' from the Left 43: * = 'R': apply Q or Q' from the Right 44: * 45: * TRANS (input) CHARACTER*1 46: * = 'N': apply Q (No transpose) 47: * = 'T': apply Q' (Transpose) 48: * 49: * M (input) INTEGER 50: * The number of rows of the matrix C. M >= 0. 51: * 52: * N (input) INTEGER 53: * The number of columns of the matrix C. N >= 0. 54: * 55: * K (input) INTEGER 56: * The number of elementary reflectors whose product defines 57: * the matrix Q. 58: * If SIDE = 'L', M >= K >= 0; 59: * if SIDE = 'R', N >= K >= 0. 60: * 61: * A (input) DOUBLE PRECISION array, dimension 62: * (LDA,M) if SIDE = 'L', 63: * (LDA,N) if SIDE = 'R' 64: * The i-th row must contain the vector which defines the 65: * elementary reflector H(i), for i = 1,2,...,k, as returned by 66: * DGELQF in the first k rows of its array argument A. 67: * A is modified by the routine but restored on exit. 68: * 69: * LDA (input) INTEGER 70: * The leading dimension of the array A. LDA >= max(1,K). 71: * 72: * TAU (input) DOUBLE PRECISION array, dimension (K) 73: * TAU(i) must contain the scalar factor of the elementary 74: * reflector H(i), as returned by DGELQF. 75: * 76: * C (input/output) DOUBLE PRECISION array, dimension (LDC,N) 77: * On entry, the m by n matrix C. 78: * On exit, C is overwritten by Q*C or Q'*C or C*Q' or C*Q. 79: * 80: * LDC (input) INTEGER 81: * The leading dimension of the array C. LDC >= max(1,M). 82: * 83: * WORK (workspace) DOUBLE PRECISION array, dimension 84: * (N) if SIDE = 'L', 85: * (M) if SIDE = 'R' 86: * 87: * INFO (output) INTEGER 88: * = 0: successful exit 89: * < 0: if INFO = -i, the i-th argument had an illegal value 90: * 91: * ===================================================================== 92: * 93: * .. Parameters .. 94: DOUBLE PRECISION ONE 95: PARAMETER ( ONE = 1.0D+0 ) 96: * .. 97: * .. Local Scalars .. 98: LOGICAL LEFT, NOTRAN 99: INTEGER I, I1, I2, I3, IC, JC, MI, NI, NQ 100: DOUBLE PRECISION AII 101: * .. 102: * .. External Functions .. 103: LOGICAL LSAME 104: EXTERNAL LSAME 105: * .. 106: * .. External Subroutines .. 107: EXTERNAL DLARF, XERBLA 108: * .. 109: * .. Intrinsic Functions .. 110: INTRINSIC MAX 111: * .. 112: * .. Executable Statements .. 113: * 114: * Test the input arguments 115: * 116: INFO = 0 117: LEFT = LSAME( SIDE, 'L' ) 118: NOTRAN = LSAME( TRANS, 'N' ) 119: * 120: * NQ is the order of Q 121: * 122: IF( LEFT ) THEN 123: NQ = M 124: ELSE 125: NQ = N 126: END IF 127: IF( .NOT.LEFT .AND. .NOT.LSAME( SIDE, 'R' ) ) THEN 128: INFO = -1 129: ELSE IF( .NOT.NOTRAN .AND. .NOT.LSAME( TRANS, 'T' ) ) THEN 130: INFO = -2 131: ELSE IF( M.LT.0 ) THEN 132: INFO = -3 133: ELSE IF( N.LT.0 ) THEN 134: INFO = -4 135: ELSE IF( K.LT.0 .OR. K.GT.NQ ) THEN 136: INFO = -5 137: ELSE IF( LDA.LT.MAX( 1, K ) ) THEN 138: INFO = -7 139: ELSE IF( LDC.LT.MAX( 1, M ) ) THEN 140: INFO = -10 141: END IF 142: IF( INFO.NE.0 ) THEN 143: CALL XERBLA( 'DORML2', -INFO ) 144: RETURN 145: END IF 146: * 147: * Quick return if possible 148: * 149: IF( M.EQ.0 .OR. N.EQ.0 .OR. K.EQ.0 ) 150: $ RETURN 151: * 152: IF( ( LEFT .AND. NOTRAN ) .OR. ( .NOT.LEFT .AND. .NOT.NOTRAN ) ) 153: $ THEN 154: I1 = 1 155: I2 = K 156: I3 = 1 157: ELSE 158: I1 = K 159: I2 = 1 160: I3 = -1 161: END IF 162: * 163: IF( LEFT ) THEN 164: NI = N 165: JC = 1 166: ELSE 167: MI = M 168: IC = 1 169: END IF 170: * 171: DO 10 I = I1, I2, I3 172: IF( LEFT ) THEN 173: * 174: * H(i) is applied to C(i:m,1:n) 175: * 176: MI = M - I + 1 177: IC = I 178: ELSE 179: * 180: * H(i) is applied to C(1:m,i:n) 181: * 182: NI = N - I + 1 183: JC = I 184: END IF 185: * 186: * Apply H(i) 187: * 188: AII = A( I, I ) 189: A( I, I ) = ONE 190: CALL DLARF( SIDE, MI, NI, A( I, I ), LDA, TAU( I ), 191: $ C( IC, JC ), LDC, WORK ) 192: A( I, I ) = AII 193: 10 CONTINUE 194: RETURN 195: * 196: * End of DORML2 197: * 198: END