1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
|
########################################################################
##
## Copyright (C) 2016-2024 The Octave Project Developers
##
## See the file COPYRIGHT.md in the top-level directory of this
## distribution or <https://octave.org/copyright/>.
##
## This file is part of Octave.
##
## Octave is free software: you can redistribute it and/or modify it
## under the terms of the GNU General Public License as published by
## the Free Software Foundation, either version 3 of the License, or
## (at your option) any later version.
##
## Octave is distributed in the hope that it will be useful, but
## WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
## GNU General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with Octave; see the file COPYING. If not, see
## <https://www.gnu.org/licenses/>.
##
########################################################################
## -*- texinfo -*-
## @deftypefn {} {[@var{Afcn}, @var{M1fcn}, @var{M2fcn}] =} __alltohandles__ (@var{A}, @var{b}, @var{M1}, @var{M2}, @var{solver_name})
##
## Check if the parameters @var{A} (matrix of our linear system), @var{b}
## (right hand side vector), @var{M1}, @var{M2} (preconditioner matrices) are
## really matrices or functions handle, summarizing if they are void or not.
##
## The input parameters are:
##
## @itemize
## @item @var{A} is the matrix of the linear system.
##
## @item @var{b} is the right hand side vector.
##
## @item @var{M1}, @var{M2} preconditioners. They can be [].
##
## @item @var{solver_name} is the name of the solver as string.
##
## @end itemize
##
## The output parameters are:
##
## @itemize
##
## @item @var{Afcn}, @var{M1fcn}, @var{M2fcn} are the corresponding
## function handles.
##
## @end itemize
## @end deftypefn
function [Afcn, M1fcn, M2fcn] = __alltohandles__ (A, b, M1, M2, solver_name)
A_is_numeric = false;
M1_is_numeric = false;
M2_is_numeric = false;
## Check A and set its type
if (is_function_handle (A))
Afcn = A;
elseif (ischar (A))
Afcn = str2func (A);
elseif (! isnumeric (A) || ! issquare (A))
error ([solver_name, ": A must be a square matrix or a function handle"]);
else
A_is_numeric = true;
if (columns (A) != rows (b))
error ("__alltohandles__: dimension of B is not consistent with A");
endif
endif
## Check M1 and sets its type
if (isempty (M1)) # M1 empty, set to identity function
switch (solver_name)
case {"pcg", "gmres", "bicgstab", "cgs", "tfqmr"}
## methods which do not require the transpose
M1fcn = @(x) x;
case {"bicg"}
## methods allow a variable number of arguments
M1fcn = @(x, varargin) x;
otherwise
error (["__alltohandles__: unknown method: ", solver_name]);
endswitch
else # M1 not empty
if (is_function_handle (M1))
M1fcn = M1;
elseif (ischar (M1))
M1fcn = str2func (M1);
elseif (! isnumeric (M1) || ! issquare (M1))
error ([solver_name, ": M1 must be a square matrix or a function handle"]);
else
M1_is_numeric = true;
endif
endif
if (isempty (M2)) # M2 empty, then I set is to the identity function
switch (solver_name)
case {"pcg", "gmres", "bicgstab", "cgs", "tfqmr"}
## methods which do not require the transpose
M2fcn = @(x) x;
case {"bicg"}
## methods allow a variable number of arguments
M2fcn = @(x, varargin) x;
otherwise
error (["__alltohandles__: unknown method: ", solver_name]);
endswitch
else # M2 not empty
if (is_function_handle (M2))
M2fcn = M2;
elseif (ischar (M2))
M2fcn = str2func (M2);
elseif (! isnumeric (M2) || ! issquare (M2))
error ([solver_name, ": M2 must be a square matrix or a function handle"]);
else
M2_is_numeric = true;
endif
endif
switch (solver_name)
case {"pcg", "gmres", "bicgstab", "cgs", "tfqmr"}
## methods which do not require the transpose
if (A_is_numeric)
Afcn = @(x) A * x;
endif
if (M1_is_numeric)
M1fcn = @(x) M1 \ x;
endif
if (M2_is_numeric)
M2fcn = @(x) M2 \ x;
endif
case {"bicg"}
## methods which require the transpose and allow a variable number of
## arguments
if (A_is_numeric)
Afcn = @(x, trans, varargin) A_sub (A, x, trans);
endif
if (M1_is_numeric)
M1fcn = @(x, trans, varargin) M_sub (M1, x, trans);
endif
if (M2_is_numeric)
M2fcn = @(x, trans, varargin) M_sub (M2, x, trans);
endif
otherwise
error (["__alltohandles__: unknown method: ", solver_name]);
endswitch
endfunction
function y = A_sub (A, x, trans)
if (strcmp (trans, "transp"))
y = A' * x;
else
y = A * x;
endif
endfunction
function y = M_sub (M, x, trans)
if (strcmp (trans, "transp"))
y = M' \ x;
else
y = M \ x;
endif
endfunction
|
