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Mise à jour de lapack vers la version 3.3.0.
1: SUBROUTINE ZUNMRQ( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, 2: $ WORK, LWORK, 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, LWORK, M, N 12: * .. 13: * .. Array Arguments .. 14: COMPLEX*16 A( LDA, * ), C( LDC, * ), TAU( * ), WORK( * ) 15: * .. 16: * 17: * Purpose 18: * ======= 19: * 20: * ZUNMRQ overwrites the general complex M-by-N matrix C with 21: * 22: * SIDE = 'L' SIDE = 'R' 23: * TRANS = 'N': Q * C C * Q 24: * TRANS = 'C': Q**H * C C * Q**H 25: * 26: * where Q is a complex unitary matrix defined as the product of k 27: * elementary reflectors 28: * 29: * Q = H(1)' H(2)' . . . H(k)' 30: * 31: * as returned by ZGERQF. Q is of order M if SIDE = 'L' and of order N 32: * if SIDE = 'R'. 33: * 34: * Arguments 35: * ========= 36: * 37: * SIDE (input) CHARACTER*1 38: * = 'L': apply Q or Q**H from the Left; 39: * = 'R': apply Q or Q**H from the Right. 40: * 41: * TRANS (input) CHARACTER*1 42: * = 'N': No transpose, apply Q; 43: * = 'C': Transpose, apply Q**H. 44: * 45: * M (input) INTEGER 46: * The number of rows of the matrix C. M >= 0. 47: * 48: * N (input) INTEGER 49: * The number of columns of the matrix C. N >= 0. 50: * 51: * K (input) INTEGER 52: * The number of elementary reflectors whose product defines 53: * the matrix Q. 54: * If SIDE = 'L', M >= K >= 0; 55: * if SIDE = 'R', N >= K >= 0. 56: * 57: * A (input) COMPLEX*16 array, dimension 58: * (LDA,M) if SIDE = 'L', 59: * (LDA,N) if SIDE = 'R' 60: * The i-th row must contain the vector which defines the 61: * elementary reflector H(i), for i = 1,2,...,k, as returned by 62: * ZGERQF in the last k rows of its array argument A. 63: * A is modified by the routine but restored on exit. 64: * 65: * LDA (input) INTEGER 66: * The leading dimension of the array A. LDA >= max(1,K). 67: * 68: * TAU (input) COMPLEX*16 array, dimension (K) 69: * TAU(i) must contain the scalar factor of the elementary 70: * reflector H(i), as returned by ZGERQF. 71: * 72: * C (input/output) COMPLEX*16 array, dimension (LDC,N) 73: * On entry, the M-by-N matrix C. 74: * On exit, C is overwritten by Q*C or Q**H*C or C*Q**H or C*Q. 75: * 76: * LDC (input) INTEGER 77: * The leading dimension of the array C. LDC >= max(1,M). 78: * 79: * WORK (workspace/output) COMPLEX*16 array, dimension (MAX(1,LWORK)) 80: * On exit, if INFO = 0, WORK(1) returns the optimal LWORK. 81: * 82: * LWORK (input) INTEGER 83: * The dimension of the array WORK. 84: * If SIDE = 'L', LWORK >= max(1,N); 85: * if SIDE = 'R', LWORK >= max(1,M). 86: * For optimum performance LWORK >= N*NB if SIDE = 'L', and 87: * LWORK >= M*NB if SIDE = 'R', where NB is the optimal 88: * blocksize. 89: * 90: * If LWORK = -1, then a workspace query is assumed; the routine 91: * only calculates the optimal size of the WORK array, returns 92: * this value as the first entry of the WORK array, and no error 93: * message related to LWORK is issued by XERBLA. 94: * 95: * INFO (output) INTEGER 96: * = 0: successful exit 97: * < 0: if INFO = -i, the i-th argument had an illegal value 98: * 99: * ===================================================================== 100: * 101: * .. Parameters .. 102: INTEGER NBMAX, LDT 103: PARAMETER ( NBMAX = 64, LDT = NBMAX+1 ) 104: * .. 105: * .. Local Scalars .. 106: LOGICAL LEFT, LQUERY, NOTRAN 107: CHARACTER TRANST 108: INTEGER I, I1, I2, I3, IB, IINFO, IWS, LDWORK, LWKOPT, 109: $ MI, NB, NBMIN, NI, NQ, NW 110: * .. 111: * .. Local Arrays .. 112: COMPLEX*16 T( LDT, NBMAX ) 113: * .. 114: * .. External Functions .. 115: LOGICAL LSAME 116: INTEGER ILAENV 117: EXTERNAL LSAME, ILAENV 118: * .. 119: * .. External Subroutines .. 120: EXTERNAL XERBLA, ZLARFB, ZLARFT, ZUNMR2 121: * .. 122: * .. Intrinsic Functions .. 123: INTRINSIC MAX, MIN 124: * .. 125: * .. Executable Statements .. 126: * 127: * Test the input arguments 128: * 129: INFO = 0 130: LEFT = LSAME( SIDE, 'L' ) 131: NOTRAN = LSAME( TRANS, 'N' ) 132: LQUERY = ( LWORK.EQ.-1 ) 133: * 134: * NQ is the order of Q and NW is the minimum dimension of WORK 135: * 136: IF( LEFT ) THEN 137: NQ = M 138: NW = MAX( 1, N ) 139: ELSE 140: NQ = N 141: NW = MAX( 1, M ) 142: END IF 143: IF( .NOT.LEFT .AND. .NOT.LSAME( SIDE, 'R' ) ) THEN 144: INFO = -1 145: ELSE IF( .NOT.NOTRAN .AND. .NOT.LSAME( TRANS, 'C' ) ) THEN 146: INFO = -2 147: ELSE IF( M.LT.0 ) THEN 148: INFO = -3 149: ELSE IF( N.LT.0 ) THEN 150: INFO = -4 151: ELSE IF( K.LT.0 .OR. K.GT.NQ ) THEN 152: INFO = -5 153: ELSE IF( LDA.LT.MAX( 1, K ) ) THEN 154: INFO = -7 155: ELSE IF( LDC.LT.MAX( 1, M ) ) THEN 156: INFO = -10 157: END IF 158: * 159: IF( INFO.EQ.0 ) THEN 160: IF( M.EQ.0 .OR. N.EQ.0 ) THEN 161: LWKOPT = 1 162: ELSE 163: * 164: * Determine the block size. NB may be at most NBMAX, where 165: * NBMAX is used to define the local array T. 166: * 167: NB = MIN( NBMAX, ILAENV( 1, 'ZUNMRQ', SIDE // TRANS, M, N, 168: $ K, -1 ) ) 169: LWKOPT = NW*NB 170: END IF 171: WORK( 1 ) = LWKOPT 172: * 173: IF( LWORK.LT.NW .AND. .NOT.LQUERY ) THEN 174: INFO = -12 175: END IF 176: END IF 177: * 178: IF( INFO.NE.0 ) THEN 179: CALL XERBLA( 'ZUNMRQ', -INFO ) 180: RETURN 181: ELSE IF( LQUERY ) THEN 182: RETURN 183: END IF 184: * 185: * Quick return if possible 186: * 187: IF( M.EQ.0 .OR. N.EQ.0 ) THEN 188: RETURN 189: END IF 190: * 191: NBMIN = 2 192: LDWORK = NW 193: IF( NB.GT.1 .AND. NB.LT.K ) THEN 194: IWS = NW*NB 195: IF( LWORK.LT.IWS ) THEN 196: NB = LWORK / LDWORK 197: NBMIN = MAX( 2, ILAENV( 2, 'ZUNMRQ', SIDE // TRANS, M, N, K, 198: $ -1 ) ) 199: END IF 200: ELSE 201: IWS = NW 202: END IF 203: * 204: IF( NB.LT.NBMIN .OR. NB.GE.K ) THEN 205: * 206: * Use unblocked code 207: * 208: CALL ZUNMR2( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK, 209: $ IINFO ) 210: ELSE 211: * 212: * Use blocked code 213: * 214: IF( ( LEFT .AND. .NOT.NOTRAN ) .OR. 215: $ ( .NOT.LEFT .AND. NOTRAN ) ) THEN 216: I1 = 1 217: I2 = K 218: I3 = NB 219: ELSE 220: I1 = ( ( K-1 ) / NB )*NB + 1 221: I2 = 1 222: I3 = -NB 223: END IF 224: * 225: IF( LEFT ) THEN 226: NI = N 227: ELSE 228: MI = M 229: END IF 230: * 231: IF( NOTRAN ) THEN 232: TRANST = 'C' 233: ELSE 234: TRANST = 'N' 235: END IF 236: * 237: DO 10 I = I1, I2, I3 238: IB = MIN( NB, K-I+1 ) 239: * 240: * Form the triangular factor of the block reflector 241: * H = H(i+ib-1) . . . H(i+1) H(i) 242: * 243: CALL ZLARFT( 'Backward', 'Rowwise', NQ-K+I+IB-1, IB, 244: $ A( I, 1 ), LDA, TAU( I ), T, LDT ) 245: IF( LEFT ) THEN 246: * 247: * H or H' is applied to C(1:m-k+i+ib-1,1:n) 248: * 249: MI = M - K + I + IB - 1 250: ELSE 251: * 252: * H or H' is applied to C(1:m,1:n-k+i+ib-1) 253: * 254: NI = N - K + I + IB - 1 255: END IF 256: * 257: * Apply H or H' 258: * 259: CALL ZLARFB( SIDE, TRANST, 'Backward', 'Rowwise', MI, NI, 260: $ IB, A( I, 1 ), LDA, T, LDT, C, LDC, WORK, 261: $ LDWORK ) 262: 10 CONTINUE 263: END IF 264: WORK( 1 ) = LWKOPT 265: RETURN 266: * 267: * End of ZUNMRQ 268: * 269: END