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Mise à jour de lapack vers la version 3.3.0.
1: SUBROUTINE ZPOTRS( UPLO, N, NRHS, A, LDA, B, LDB, INFO ) 2: * 3: * -- LAPACK routine (version 3.2) -- 4: * -- LAPACK is a software package provided by Univ. of Tennessee, -- 5: * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- 6: * November 2006 7: * 8: * .. Scalar Arguments .. 9: CHARACTER UPLO 10: INTEGER INFO, LDA, LDB, N, NRHS 11: * .. 12: * .. Array Arguments .. 13: COMPLEX*16 A( LDA, * ), B( LDB, * ) 14: * .. 15: * 16: * Purpose 17: * ======= 18: * 19: * ZPOTRS solves a system of linear equations A*X = B with a Hermitian 20: * positive definite matrix A using the Cholesky factorization 21: * A = U**H*U or A = L*L**H computed by ZPOTRF. 22: * 23: * Arguments 24: * ========= 25: * 26: * UPLO (input) CHARACTER*1 27: * = 'U': Upper triangle of A is stored; 28: * = 'L': Lower triangle of A is stored. 29: * 30: * N (input) INTEGER 31: * The order of the matrix A. N >= 0. 32: * 33: * NRHS (input) INTEGER 34: * The number of right hand sides, i.e., the number of columns 35: * of the matrix B. NRHS >= 0. 36: * 37: * A (input) COMPLEX*16 array, dimension (LDA,N) 38: * The triangular factor U or L from the Cholesky factorization 39: * A = U**H*U or A = L*L**H, as computed by ZPOTRF. 40: * 41: * LDA (input) INTEGER 42: * The leading dimension of the array A. LDA >= max(1,N). 43: * 44: * B (input/output) COMPLEX*16 array, dimension (LDB,NRHS) 45: * On entry, the right hand side matrix B. 46: * On exit, the solution matrix X. 47: * 48: * LDB (input) INTEGER 49: * The leading dimension of the array B. LDB >= max(1,N). 50: * 51: * INFO (output) INTEGER 52: * = 0: successful exit 53: * < 0: if INFO = -i, the i-th argument had an illegal value 54: * 55: * ===================================================================== 56: * 57: * .. Parameters .. 58: COMPLEX*16 ONE 59: PARAMETER ( ONE = ( 1.0D+0, 0.0D+0 ) ) 60: * .. 61: * .. Local Scalars .. 62: LOGICAL UPPER 63: * .. 64: * .. External Functions .. 65: LOGICAL LSAME 66: EXTERNAL LSAME 67: * .. 68: * .. External Subroutines .. 69: EXTERNAL XERBLA, ZTRSM 70: * .. 71: * .. Intrinsic Functions .. 72: INTRINSIC MAX 73: * .. 74: * .. Executable Statements .. 75: * 76: * Test the input parameters. 77: * 78: INFO = 0 79: UPPER = LSAME( UPLO, 'U' ) 80: IF( .NOT.UPPER .AND. .NOT.LSAME( UPLO, 'L' ) ) THEN 81: INFO = -1 82: ELSE IF( N.LT.0 ) THEN 83: INFO = -2 84: ELSE IF( NRHS.LT.0 ) THEN 85: INFO = -3 86: ELSE IF( LDA.LT.MAX( 1, N ) ) THEN 87: INFO = -5 88: ELSE IF( LDB.LT.MAX( 1, N ) ) THEN 89: INFO = -7 90: END IF 91: IF( INFO.NE.0 ) THEN 92: CALL XERBLA( 'ZPOTRS', -INFO ) 93: RETURN 94: END IF 95: * 96: * Quick return if possible 97: * 98: IF( N.EQ.0 .OR. NRHS.EQ.0 ) 99: $ RETURN 100: * 101: IF( UPPER ) THEN 102: * 103: * Solve A*X = B where A = U'*U. 104: * 105: * Solve U'*X = B, overwriting B with X. 106: * 107: CALL ZTRSM( 'Left', 'Upper', 'Conjugate transpose', 'Non-unit', 108: $ N, NRHS, ONE, A, LDA, B, LDB ) 109: * 110: * Solve U*X = B, overwriting B with X. 111: * 112: CALL ZTRSM( 'Left', 'Upper', 'No transpose', 'Non-unit', N, 113: $ NRHS, ONE, A, LDA, B, LDB ) 114: ELSE 115: * 116: * Solve A*X = B where A = L*L'. 117: * 118: * Solve L*X = B, overwriting B with X. 119: * 120: CALL ZTRSM( 'Left', 'Lower', 'No transpose', 'Non-unit', N, 121: $ NRHS, ONE, A, LDA, B, LDB ) 122: * 123: * Solve L'*X = B, overwriting B with X. 124: * 125: CALL ZTRSM( 'Left', 'Lower', 'Conjugate transpose', 'Non-unit', 126: $ N, NRHS, ONE, A, LDA, B, LDB ) 127: END IF 128: * 129: RETURN 130: * 131: * End of ZPOTRS 132: * 133: END