annotate scripts/general/pol2cart.m @ 9168:742cf6388a8f

Update section 17.7 (Coordinate Transformations) of arith.txi
author Rik <rdrider0-list@yahoo.com>
date Sat, 02 May 2009 07:20:35 -0700
parents eb63fbe60fab
children 7357e37f34fa
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
8920
eb63fbe60fab update copyright notices
John W. Eaton <jwe@octave.org>
parents: 8533
diff changeset
1 ## Copyright (C) 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009 Kai Habel
3803
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
2 ##
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
3 ## This file is part of Octave.
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
4 ##
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
5 ## Octave is free software; you can redistribute it and/or modify it
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
6 ## under the terms of the GNU General Public License as published by
7016
93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe]
jwe
parents: 6898
diff changeset
7 ## the Free Software Foundation; either version 3 of the License, or (at
93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe]
jwe
parents: 6898
diff changeset
8 ## your option) any later version.
3803
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
9 ##
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
10 ## Octave is distributed in the hope that it will be useful, but
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
11 ## WITHOUT ANY WARRANTY; without even the implied warranty of
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
13 ## General Public License for more details.
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
14 ##
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
15 ## You should have received a copy of the GNU General Public License
7016
93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe]
jwe
parents: 6898
diff changeset
16 ## along with Octave; see the file COPYING. If not, see
93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe]
jwe
parents: 6898
diff changeset
17 ## <http://www.gnu.org/licenses/>.
3803
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
18
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
19 ## -*- texinfo -*-
5610
9761b7d24e9e [project @ 2006-02-09 09:12:02 by dbateman]
dbateman
parents: 5307
diff changeset
20 ## @deftypefn {Function File} {[@var{x}, @var{y}] =} pol2cart (@var{theta}, @var{r})
9761b7d24e9e [project @ 2006-02-09 09:12:02 by dbateman]
dbateman
parents: 5307
diff changeset
21 ## @deftypefnx {Function File} {[@var{x}, @var{y}, @var{z}] =} pol2cart (@var{theta}, @var{r}, @var{z})
9168
742cf6388a8f Update section 17.7 (Coordinate Transformations) of arith.txi
Rik <rdrider0-list@yahoo.com>
parents: 8920
diff changeset
22 ## Transform polar or cylindrical to Cartesian coordinates.
742cf6388a8f Update section 17.7 (Coordinate Transformations) of arith.txi
Rik <rdrider0-list@yahoo.com>
parents: 8920
diff changeset
23 ## @var{theta}, @var{r} (and @var{z}) must be the same shape, or scalar.
742cf6388a8f Update section 17.7 (Coordinate Transformations) of arith.txi
Rik <rdrider0-list@yahoo.com>
parents: 8920
diff changeset
24 ## @var{theta} describes the angle relative to the positive x-axis.
8491
aaff46fef256 [docs] fix hypenation: x - axis => x-axis, etc
Brian Gough <bjg@gnu.org>
parents: 7017
diff changeset
25 ## @var{r} is the distance to the z-axis (0, 0, z).
5642
2618a0750ae6 [project @ 2006-03-06 21:26:48 by jwe]
jwe
parents: 5610
diff changeset
26 ## @seealso{cart2pol, cart2sph, sph2cart}
3803
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
27 ## @end deftypefn
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
28
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
29 ## Author: Kai Habel <kai.habel@gmx.de>
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
30 ## Adapted-by: jwe
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
31
8533
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
32 function [x, y, z] = pol2cart (theta, r, z)
3803
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
33
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
34 if (nargin < 2 || nargin > 3)
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
35 error ("pol2cart: number of arguments must be 2 or 3");
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
36 endif
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
37
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
38 if (nargin == 2 && nargout > 2)
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
39 error ("pol2cart: number of output arguments must not be greater than number of input arguments");
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
40 endif
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
41
8533
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
42 if ((ismatrix (theta) && ismatrix (r) && (nargin == 2 || ismatrix (z)))
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
43 && (size_equal (theta, r) || isscalar (theta) || isscalar (r))
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
44 && (nargin == 2 || size_equal (theta, z) || isscalar (theta) || isscalar (z))
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
45 && (nargin == 2 || size_equal (r, z) || isscalar (r) || isscalar (z)))
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
46
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
47 x = cos (theta) .* r;
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
48 y = sin (theta) .* r;
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
49
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
50 else
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
51 error ("pol2cart: arguments must be matrices of same size, or scalar");
3803
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
52 endif
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
53
8533
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
54 endfunction
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
55
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
56 %!test
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
57 %! t = [0, 0.5, 1] * pi;
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
58 %! r = 1;
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
59 %! [x, y] = pol2cart (t, r);
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
60 %! assert (x, [1, 0, -1], sqrt(eps));
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
61 %! assert (y, [0, 1, 0], sqrt(eps));
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
62
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
63 %!test
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
64 %! t = [0, 1, 1] * pi/4;
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
65 %! r = sqrt(2) * [0, 1, 2];
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
66 %! [x, y] = pol2cart (t, r);
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
67 %! assert (x, [0, 1, 2], sqrt(eps));
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
68 %! assert (y, [0, 1, 2], sqrt(eps));
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
69
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
70 %!test
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
71 %! t = [0, 1, 1] * pi/4;
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
72 %! r = sqrt(2) * [0, 1, 2];
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
73 %! z = [0, 1, 2];
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
74 %! [x, y, z2] = pol2cart (t, r, z);
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
75 %! assert (x, [0, 1, 2], sqrt(eps));
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
76 %! assert (y, [0, 1, 2], sqrt(eps));
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
77 %! assert (z, z2);
3803
63c75bc3db82 [project @ 2001-02-28 08:24:40 by jwe]
jwe
parents:
diff changeset
78
8533
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
79 %!test
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
80 %! t = 0;
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
81 %! r = [0, 1, 2];
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
82 %! z = [0, 1, 2];
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
83 %! [x, y, z2] = pol2cart (t, r, z);
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
84 %! assert (x, [0, 1, 2], sqrt(eps));
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
85 %! assert (y, [0, 0, 0], sqrt(eps));
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
86 %! assert (z, z2);
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
87
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
88 %!test
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
89 %! t = [1, 1, 1]*pi/4;
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
90 %! r = 1;
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
91 %! z = [0, 1, 2];
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
92 %! [x, y, z2] = pol2cart (t, r, z);
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
93 %! assert (x, [1, 1, 1] / sqrt(2), eps);
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
94 %! assert (y, [1, 1, 1] / sqrt(2), eps);
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
95 %! assert (z, z2);
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
96
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
97 %!test
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
98 %! t = 0;
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
99 %! r = [1, 2, 3];
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
100 %! z = 1;
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
101 %! [x, y, z2] = pol2cart (t, r, z);
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
102 %! assert (x, [1, 2, 3], eps);
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
103 %! assert (y, [0, 0, 0] / sqrt(2), eps);
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
104 %! assert (z, z2);
fb1b87ea4af9 Permit scalars when transforming coordinates.
Ben Abbott <bpabbott@mac.com>
parents: 8507
diff changeset
105