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az_ifpack_iterate.c
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42 
43 /*
44  * This code is a wrapper layer around AZTEC. It takes the real and imaginary
45  * parts of a complex valued linear system and forms an equivalent real system,
46  * calls AZTEC to solve the real system and returns the solution.
47  */
48 
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <math.h>
52 #include <std::string.h>
53 #include "az_aztec.h"
54 #include "az_ifpack.h"
55 
56 void AZ_ifpack_iterate(double *x, double *b,
57  int *options, double *params,
58  double *status, int *proc_config,
59  AZ_MATRIX *Amat )
60 
61 /*******************************************************************************
62 
63  Author: Mike Heroux, SNL, 9222
64  =======
65 
66  Return code: void
67  ============
68 
69  Parameter list:
70  ===============
71 
72  x: On input, contains the initial guess, On output
73  contains the solution to
74  the linear system.
75 
76  b: Right hand side of linear system.
77 
78  options: Determines specific solution method and other parameters.
79 
80  params: Drop tolerance and convergence tolerance info.
81 
82  status: On output, indicates termination status:
83  0: terminated normally.
84  -1: maximum number of iterations taken without achieving
85  convergence.
86  -2: Breakdown. The algorithm can not proceed due to
87  numerical difficulties (usually a divide by zero).
88  -3: Internal residual differs from the computed residual due
89  to a significant loss of precision.
90 
91  proc_config: Machine configuration. proc_config[AZ_node] is the node
92  number. proc_config[AZ_N_procs] is the number of processors.
93 
94  Amat: The matrix operator, stored as an AZ_MATRIX structure.
95 
96  Internal Parameter list:
97  ========================
98 
99  x: Komplex version of initial guess and solution.
100  b: Komplex version of RHS.
101  Prec: Preconditioner stored as an AZ_PRECOND structure.
102 
103  Overview
104  ========
105 
106 *******************************************************************************/
107 
108 
109 {
110 
111 AZ_PRECOND *Prec; /* Structure representing entire preconditioner. */
112  /* */
113 
114  AZ_ifpack_prec_create (x, b, options, params, proc_config, Amat, &Prec);
115 
116  /* solve linear system using Aztec. */
117 
118  AZ_iterate(x, b, options, params, status, proc_config, Amat, Prec, NULL);
119 
120  AZ_ifpack_prec_destroy (options, params, proc_config, Amat, Prec);
121 
122 /* AZ_ifpack_iterate*/
123 }