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Deprecate luinc. * NEWS: Announce deprecation * luinc.cc (F__luinc__): Rename luinc to internal function __luinc__. * scripts/deprecated/luinc.m: New m-file to issue deprecation warning. * scripts/deprecated/module.mk: Add luinc.m to build system. * sparse.txi: Remove function from manual. * pcg.m: Replace luinc example in docstring with ilu.
author Rik <rik@octave.org>
date Mon, 22 Sep 2014 20:19:01 -0700
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children 71da5cce37d6
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19147:8b2a919d24bc 19148:e278c939a419
1 ## Copyright (C) 2014 John W. Eaton
2 ##
3 ## This file is part of Octave.
4 ##
5 ## Octave is free software; you can redistribute it and/or modify it
6 ## under the terms of the GNU General Public License as published by
7 ## the Free Software Foundation; either version 3 of the License, or (at
8 ## your option) any later version.
9 ##
10 ## Octave is distributed in the hope that it will be useful, but
11 ## WITHOUT ANY WARRANTY; without even the implied warranty of
12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 ## General Public License for more details.
14 ##
15 ## You should have received a copy of the GNU General Public License
16 ## along with Octave; see the file COPYING. If not, see
17 ## <http://www.gnu.org/licenses/>.
18
19 ## @deftypefn {Built-in Function} {[@var{L}, @var{U}, @var{P}, @var{Q}] =} luinc (@var{A}, '0')
20 ## @deftypefnx {Built-in Function} {[@var{L}, @var{U}, @var{P}, @var{Q}] =} luinc (@var{A}, @var{droptol})
21 ## @deftypefnx {Built-in Function} {[@var{L}, @var{U}, @var{P}, @var{Q}] =} luinc (@var{A}, @var{opts})
22 ##
23 ## @code{luinc} is deprecated and will be removed in Octave version 4.6.
24 ## Please use @code{ilu} or @code{ichol} in all new code.
25 ##
26 ## Produce the incomplete LU@tie{}factorization of the sparse matrix @var{A}.
27 ## Two types of incomplete factorization are possible, and the type
28 ## is determined by the second argument to @code{luinc}.
29 ##
30 ## Called with a second argument of @qcode{'0'}, the zero-level incomplete
31 ## LU@tie{}factorization is produced. This creates a factorization of @var{A}
32 ## where the position of the nonzero arguments correspond to the same
33 ## positions as in the matrix @var{A}.
34 ##
35 ## Alternatively, the fill-in of the incomplete LU@tie{}factorization can
36 ## be controlled through the variable @var{droptol} or the structure
37 ## @var{opts}. The @sc{umfpack} multifrontal factorization code by Tim A.
38 ## Davis is used for the incomplete LU@tie{}factorization, (availability
39 ## @url{http://www.cise.ufl.edu/research/sparse/umfpack/})
40 ##
41 ## @var{droptol} determines the values below which the values in the
42 ## LU@tie{} factorization are dropped and replaced by zero. It must be a
43 ## positive scalar, and any values in the factorization whose absolute value
44 ## are less than this value are dropped, expect if leaving them increase the
45 ## sparsity of the matrix. Setting @var{droptol} to zero results in a complete
46 ## LU@tie{}factorization which is the default.
47 ##
48 ## @var{opts} is a structure containing one or more of the fields
49 ##
50 ## @table @code
51 ## @item droptol
52 ## The drop tolerance as above. If @var{opts} only contains @code{droptol}
53 ## then this is equivalent to using the variable @var{droptol}.
54 ##
55 ## @item milu
56 ## A logical variable flagging whether to use the modified incomplete
57 ## LU@tie{} factorization. In the case that @code{milu} is true, the dropped
58 ## values are subtracted from the diagonal of the matrix @var{U} of the
59 ## factorization. The default is @code{false}.
60 ##
61 ## @item udiag
62 ## A logical variable that flags whether zero elements on the diagonal of
63 ## @var{U} should be replaced with @var{droptol} to attempt to avoid singular
64 ## factors. The default is @code{false}.
65 ##
66 ## @item thresh
67 ## Defines the pivot threshold in the interval [0,1]. Values outside that
68 ## range are ignored.
69 ## @end table
70 ##
71 ## All other fields in @var{opts} are ignored. The outputs from @code{luinc}
72 ## are the same as for @code{lu}.
73 ##
74 ## Given the string argument @qcode{\"vector\"}, @code{luinc} returns the
75 ## values of @var{p} @var{q} as vector values.
76 ## @seealso{ilu, ichol, lu, sparse}
77 ## @end deftypefn
78
79 ## Deprecated in version 4.2
80
81 function retval = usage (varargin)
82
83 persistent warned = false;
84 if (! warned)
85 warned = true;
86 warning ("Octave:deprecated-function",
87 "luinc is obsolete and will be removed from a future version of Octave, please use ilu or ichol instead");
88 endif
89
90 retval = __luinc__ (varargin{:});
91
92 endfunction
93