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Matlab compatibility fixes for coordinate transform functions (bug #57794). * cart2pol.m, cart2sph.m, pol2cart.m, sph2cart.m: Modified to allow row or column vector inputs, remove full matrix single output argument option, and clarified coordinate definitions in help text. * lightangle.m, surfl.m: Fix existing instances where single output was used and a matrix was expected. * NEWS: Added coordinate transform changes to Matlab compatibility section.
author Nicholas R. Jankowski <jankowskin@asme.org>
date Sun, 16 Feb 2020 20:19:05 -0500
parents a4268efb7334
children 28de41192f3c
comparison
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28170:5e49ba5bdcc1 28171:a23da76e0693
26 ## -*- texinfo -*- 26 ## -*- texinfo -*-
27 ## @deftypefn {} {[@var{theta}, @var{r}] =} cart2pol (@var{x}, @var{y}) 27 ## @deftypefn {} {[@var{theta}, @var{r}] =} cart2pol (@var{x}, @var{y})
28 ## @deftypefnx {} {[@var{theta}, @var{r}, @var{z}] =} cart2pol (@var{x}, @var{y}, @var{z}) 28 ## @deftypefnx {} {[@var{theta}, @var{r}, @var{z}] =} cart2pol (@var{x}, @var{y}, @var{z})
29 ## @deftypefnx {} {[@var{theta}, @var{r}] =} cart2pol (@var{C}) 29 ## @deftypefnx {} {[@var{theta}, @var{r}] =} cart2pol (@var{C})
30 ## @deftypefnx {} {[@var{theta}, @var{r}, @var{z}] =} cart2pol (@var{C}) 30 ## @deftypefnx {} {[@var{theta}, @var{r}, @var{z}] =} cart2pol (@var{C})
31 ## @deftypefnx {} {@var{P} =} cart2pol (@dots{})
32 ## 31 ##
33 ## Transform Cartesian coordinates to polar or cylindrical coordinates. 32 ## Transform Cartesian coordinates to polar or cylindrical coordinates.
34 ## 33 ##
35 ## The inputs @var{x}, @var{y} (, and @var{z}) must be the same shape, or 34 ## The inputs @var{x}, @var{y} (, and @var{z}) must be the same shape, or
36 ## scalar. If called with a single matrix argument then each row of @var{C} 35 ## scalar. If called with a single matrix argument then each row of @var{C}
37 ## represents the Cartesian coordinate (@var{x}, @var{y} (, @var{z})). 36 ## represents the Cartesian coordinate pair (@var{x}, @var{y}) or triplet
38 ## 37 ## (@var{x}, @var{y}, @var{z}).
39 ## @var{theta} describes the angle relative to the positive x-axis. 38 ##
39 ## The outputs @var{theta}, @var{r} (, and @var{z}) match the shape of the
40 ## inputs. For a matrix input @var{C} the outputs will be column vectors with
41 ## rows corresponding to the rows of the input matrix.
42 ##
43 ## @var{theta} describes the angle relative to the positive x-axis measured in
44 ## the xy-plane.
40 ## 45 ##
41 ## @var{r} is the distance to the z-axis @w{(0, 0, z)}. 46 ## @var{r} is the distance to the z-axis @w{(0, 0, z)}.
42 ## 47 ##
43 ## If only a single return argument is requested then return a matrix @var{P} 48 ## @var{z}, if present, is unchanged by the transformation.
44 ## where each row represents one polar/(cylindrical) coordinate 49 ##
45 ## (@var{theta}, @var{phi} (, @var{z})). 50 ## The coordinate transformation is computed using:
51 ##
52 ## @tex
53 ## $$ \theta = \arctan \left ( {y \over x} \right ) $$
54 ## $$ r = \sqrt{x^2 + y^2} $$
55 ## $$ z = z $$
56 ## @end tex
57 ## @ifnottex
58 ##
59 ## @example
60 ## @group
61 ## @var{theta} = arctan (@var{y} / @var{x})
62 ## @var{r} = sqrt (@var{x}^2 + @var{y}^2)
63 ## @var{z} = @var{z}
64 ## @end group
65 ## @end example
66 ##
67 ## @end ifnottex
68 ##
69 ## @c FIXME: Remove this note in Octave 9.1 (two releases after 7.1).
70 ## Note: For @sc{matlab} compatibility, this function no longer returns a full
71 ## coordinate matrix when called with a single return argument.
46 ## @seealso{pol2cart, cart2sph, sph2cart} 72 ## @seealso{pol2cart, cart2sph, sph2cart}
47 ## @end deftypefn 73 ## @end deftypefn
48 74
49 function [theta, r, z] = cart2pol (x, y, z = []) 75 function [theta, r, z] = cart2pol (x, y, z = [])
50 76
51 if (nargin < 1 || nargin > 3) 77 if (nargin < 1 || nargin > 3)
52 print_usage (); 78 print_usage ();
53 endif 79 endif
54 80
55 if (nargin == 1) 81 if (nargin == 1)
56 if (! (isnumeric (x) && ismatrix (x) 82 if (! (isnumeric (x) && ismatrix (x)))
57 && (columns (x) == 2 || columns (x) == 3))) 83 error ("cart2pol: matrix input must be 2-D numeric array");
58 error ("cart2pol: matrix input must have 2 or 3 columns [X, Y (, Z)]"); 84 endif
59 endif 85 if (isvector (x))
60 if (columns (x) == 3) 86 n = numel (x);
61 z = x(:,3); 87 if (n != 2 && n != 3)
62 endif 88 error ("cart2pol: matrix input must be a 2- or 3-element vector or a 2- or 3-column array");
63 y = x(:,2); 89 endif
64 x = x(:,1); 90 if (n == 3)
91 z = x(3);
92 endif
93 y = x(2);
94 x = x(1);
95 else
96 ncols = columns (x);
97 if (ncols != 2 && ncols != 3)
98 error ("cart2pol: matrix input must be a 2- or 3-element vector or a 2- or 3-column array");
99 endif
100
101 if (ncols == 3)
102 z = x(:,3);
103 endif
104 y = x(:,2);
105 x = x(:,1);
106 endif
107
65 elseif (nargin == 2) 108 elseif (nargin == 2)
66 if (! isnumeric (x) || ! isnumeric (y)) 109 if (! (isnumeric (x) && isnumeric (y)))
67 error ("cart2pol: X, Y must be numeric arrays of the same size, or scalar"); 110 error ("cart2pol: X, Y must be numeric arrays or scalars");
68 endif 111 endif
69 [err, x, y] = common_size (x, y); 112 [err, x, y] = common_size (x, y);
70 if (err) 113 if (err)
71 error ("cart2pol: X, Y must be numeric arrays of the same size, or scalar"); 114 error ("cart2pol: X, Y must be the same size or scalars");
72 endif 115 endif
116
73 elseif (nargin == 3) 117 elseif (nargin == 3)
74 if (! isnumeric (x) || ! isnumeric (y) || ! isnumeric (z)) 118 if (! (isnumeric (x) && isnumeric (y) && isnumeric (z)))
75 error ("cart2pol: X, Y, Z must be numeric arrays of the same size, or scalar"); 119 error ("cart2pol: X, Y, Z must be numeric arrays or scalars");
76 endif 120 endif
77 [err, x, y, z] = common_size (x, y, z); 121 [err, x, y, z] = common_size (x, y, z);
78 if (err) 122 if (err)
79 error ("cart2pol: X, Y, Z must be numeric arrays of the same size, or scalar"); 123 error ("cart2pol: X, Y, Z must be the same size or scalars");
80 endif 124 endif
81 endif 125 endif
82 126
83 theta = atan2 (y, x); 127 theta = atan2 (y, x);
84 r = sqrt (x .^ 2 + y .^ 2); 128 r = sqrt (x .^ 2 + y .^ 2);
85 129
86 if (nargout <= 1)
87 if (isempty (z))
88 theta = [theta(:), r(:)];
89 else
90 theta = [theta(:), r(:), z(:)];
91 endif
92 endif
93
94 endfunction 130 endfunction
95 131
96 132
97 %!test 133 %!test
98 %! x = [0, 1, 2]; 134 %! x = [0, 1, 2];
102 %! assert (r, x); 138 %! assert (r, x);
103 139
104 %!test 140 %!test
105 %! x = [0, 1, 2]; 141 %! x = [0, 1, 2];
106 %! y = [0, 1, 2]; 142 %! y = [0, 1, 2];
107 %! P = cart2pol (x, y); 143 %! [t, r] = cart2pol (x, y);
108 %! assert (P(:,1), [0; pi/4; pi/4], sqrt (eps)); 144 %! assert (t, [0, pi/4, pi/4], eps);
109 %! assert (P(:,2), sqrt (2)*[0; 1; 2], sqrt (eps)); 145 %! assert (r, sqrt (2)*[0, 1, 2], eps);
146
147 %!test
148 %! x = [0, 1, 2]';
149 %! y = [0, 1, 2]';
150 %! [t, r] = cart2pol (x, y);
151 %! assert (t, [0; pi/4; pi/4], eps);
152 %! assert (r, sqrt (2)*[0; 1; 2], eps);
110 153
111 %!test 154 %!test
112 %! x = [0, 1, 2]; 155 %! x = [0, 1, 2];
113 %! y = [0, 1, 2]; 156 %! y = [0, 1, 2];
114 %! z = [0, 1, 2]; 157 %! z = [0, 1, 2];
144 %! assert (r, [0, 0, 0]); 187 %! assert (r, [0, 0, 0]);
145 %! assert (z2, z); 188 %! assert (z2, z);
146 189
147 %!test 190 %!test
148 %! C = [0, 0; 1, 1; 2, 2]; 191 %! C = [0, 0; 1, 1; 2, 2];
149 %! P = [0, 0; pi/4, sqrt(2); pi/4, 2*sqrt(2)]; 192 %! [t, r] = cart2pol (C);
150 %! assert (cart2pol (C), P, sqrt (eps)); 193 %! assert (t, [0; 1; 1]*pi/4, eps);
194 %! assert (r, [0; 1; 2]*sqrt(2), eps);
151 195
152 %!test 196 %!test
153 %! C = [0, 0, 0; 1, 1, 1; 2, 2, 2]; 197 %! C = [0, 0, 0; 1, 1, 1; 2, 2, 2];
154 %! P = [0, 0, 0; pi/4, sqrt(2), 1; pi/4, 2*sqrt(2), 2]; 198 %! [t, r, z] = cart2pol (C);
155 %! assert (cart2pol (C), P, sqrt (eps)); 199 %! assert (t, [0; 1; 1]*pi/4, eps);
200 %! assert (r, [0; 1; 2]*sqrt(2), eps);
201 %! assert (z, [0; 1; 2]);
202
203 %!test
204 %! C = [0, 0, 0; 1, 1, 1; 2, 2, 2;1, 1, 1];
205 %! [t, r, z] = cart2pol (C);
206 %! assert (t, [0; 1; 1; 1]*pi/4, eps);
207 %! assert (r, [0; 1; 2; 1]*sqrt(2), eps);
208 %! assert (z, [0; 1; 2; 1]);
156 209
157 %!test 210 %!test
158 %! x = zeros (1, 1, 1, 2); 211 %! x = zeros (1, 1, 1, 2);
159 %! x(1, 1, 1, 2) = sqrt (2); 212 %! x(1, 1, 1, 2) = sqrt (2);
160 %! y = x; 213 %! y = x;
177 %! assert (z, Z); 230 %! assert (z, Z);
178 231
179 ## Test input validation 232 ## Test input validation
180 %!error cart2pol () 233 %!error cart2pol ()
181 %!error cart2pol (1,2,3,4) 234 %!error cart2pol (1,2,3,4)
182 %!error <matrix input must have 2 or 3 columns> cart2pol ({1,2,3}) 235 %!error <matrix input must be 2-D numeric array> cart2pol ({1,2,3})
183 %!error <matrix input must have 2 or 3 columns> cart2pol (ones (3,3,2)) 236 %!error <matrix input must be 2-D numeric array> cart2pol (ones (3,3,2))
184 %!error <matrix input must have 2 or 3 columns> cart2pol ([1]) 237 %!error <matrix input must be a 2- or 3-element> cart2pol ([1])
185 %!error <matrix input must have 2 or 3 columns> cart2pol ([1,2,3,4]) 238 %!error <matrix input must be a 2- or 3-element> cart2pol ([1,2,3,4])
186 %!error <numeric arrays of the same size> cart2pol ({1,2,3}, [1,2,3]) 239 %!error <must be numeric arrays or scalars> cart2pol ({1,2,3}, [1,2,3])
187 %!error <numeric arrays of the same size> cart2pol ([1,2,3], {1,2,3}) 240 %!error <must be numeric arrays or scalars> cart2pol ([1,2,3], {1,2,3})
188 %!error <numeric arrays of the same size> cart2pol (ones (3,3,3), ones (3,2,3)) 241 %!error <must be the same size or scalars> cart2pol (ones (3,3,3), ones (3,2,3))
189 %!error <numeric arrays of the same size> cart2pol ({1,2,3}, [1,2,3], [1,2,3]) 242 %!error <must be the same size or scalars> cart2pol ([1; 1], [2, 2])
190 %!error <numeric arrays of the same size> cart2pol ([1,2,3], {1,2,3}, [1,2,3]) 243 %!error <must be the same size or scalars> cart2pol ([1; 1], [2, 2], [3, 3])
191 %!error <numeric arrays of the same size> cart2pol ([1,2,3], [1,2,3], {1,2,3}) 244 %!error <must be numeric arrays or scalars> cart2pol ({1,2,3}, [1,2,3], [1,2,3])
192 %!error <numeric arrays of the same size> cart2pol (ones (3,3,3), 1, ones (3,2,3)) 245 %!error <must be numeric arrays or scalars> cart2pol ([1,2,3], {1,2,3}, [1,2,3])
193 %!error <numeric arrays of the same size> cart2pol (ones (3,3,3), ones (3,2,3), 1) 246 %!error <must be numeric arrays or scalars> cart2pol ([1,2,3], [1,2,3], {1,2,3})
247 %!error <must be the same size or scalars> cart2pol (ones (3,3,3), 1, ones (3,2,3))
248 %!error <must be the same size or scalars> cart2pol (ones (3,3,3), ones (3,2,3), 1)