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Mise à jour de lapack vers la version 3.3.0.
1: SUBROUTINE ZPTSV( N, NRHS, D, E, 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: INTEGER INFO, LDB, N, NRHS 10: * .. 11: * .. Array Arguments .. 12: DOUBLE PRECISION D( * ) 13: COMPLEX*16 B( LDB, * ), E( * ) 14: * .. 15: * 16: * Purpose 17: * ======= 18: * 19: * ZPTSV computes the solution to a complex system of linear equations 20: * A*X = B, where A is an N-by-N Hermitian positive definite tridiagonal 21: * matrix, and X and B are N-by-NRHS matrices. 22: * 23: * A is factored as A = L*D*L**H, and the factored form of A is then 24: * used to solve the system of equations. 25: * 26: * Arguments 27: * ========= 28: * 29: * N (input) INTEGER 30: * The order of the matrix A. N >= 0. 31: * 32: * NRHS (input) INTEGER 33: * The number of right hand sides, i.e., the number of columns 34: * of the matrix B. NRHS >= 0. 35: * 36: * D (input/output) DOUBLE PRECISION array, dimension (N) 37: * On entry, the n diagonal elements of the tridiagonal matrix 38: * A. On exit, the n diagonal elements of the diagonal matrix 39: * D from the factorization A = L*D*L**H. 40: * 41: * E (input/output) COMPLEX*16 array, dimension (N-1) 42: * On entry, the (n-1) subdiagonal elements of the tridiagonal 43: * matrix A. On exit, the (n-1) subdiagonal elements of the 44: * unit bidiagonal factor L from the L*D*L**H factorization of 45: * A. E can also be regarded as the superdiagonal of the unit 46: * bidiagonal factor U from the U**H*D*U factorization of A. 47: * 48: * B (input/output) COMPLEX*16 array, dimension (LDB,N) 49: * On entry, the N-by-NRHS right hand side matrix B. 50: * On exit, if INFO = 0, the N-by-NRHS solution matrix X. 51: * 52: * LDB (input) INTEGER 53: * The leading dimension of the array B. LDB >= max(1,N). 54: * 55: * INFO (output) INTEGER 56: * = 0: successful exit 57: * < 0: if INFO = -i, the i-th argument had an illegal value 58: * > 0: if INFO = i, the leading minor of order i is not 59: * positive definite, and the solution has not been 60: * computed. The factorization has not been completed 61: * unless i = N. 62: * 63: * ===================================================================== 64: * 65: * .. External Subroutines .. 66: EXTERNAL XERBLA, ZPTTRF, ZPTTRS 67: * .. 68: * .. Intrinsic Functions .. 69: INTRINSIC MAX 70: * .. 71: * .. Executable Statements .. 72: * 73: * Test the input parameters. 74: * 75: INFO = 0 76: IF( N.LT.0 ) THEN 77: INFO = -1 78: ELSE IF( NRHS.LT.0 ) THEN 79: INFO = -2 80: ELSE IF( LDB.LT.MAX( 1, N ) ) THEN 81: INFO = -6 82: END IF 83: IF( INFO.NE.0 ) THEN 84: CALL XERBLA( 'ZPTSV ', -INFO ) 85: RETURN 86: END IF 87: * 88: * Compute the L*D*L' (or U'*D*U) factorization of A. 89: * 90: CALL ZPTTRF( N, D, E, INFO ) 91: IF( INFO.EQ.0 ) THEN 92: * 93: * Solve the system A*X = B, overwriting B with X. 94: * 95: CALL ZPTTRS( 'Lower', N, NRHS, D, E, B, LDB, INFO ) 96: END IF 97: RETURN 98: * 99: * End of ZPTSV 100: * 101: END