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comparison scripts/sparse/sprandsym.m @ 13064:bae887ebea48

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codesprint: Add input validation and tests for sprandsym.m * sprandsym.m: Add input validation and tests for sprandsym.m. * sprandn.m: Remove unnecessary output from find()
author Rik <octave@nomad.inbox5.com>
date Sat, 03 Sep 2011 11:29:24 -0700
parents c792872f8942
children abf1e00111dd
comparison
equal deleted inserted replaced
13063:4b110dd204b9 13064:bae887ebea48
32 ## triangular part. 32 ## triangular part.
33 ## @seealso{sprand, sprandn} 33 ## @seealso{sprand, sprandn}
34 ## @end deftypefn 34 ## @end deftypefn
35 35
36 function S = sprandsym (n, d) 36 function S = sprandsym (n, d)
37 if (nargin == 1)
38 [i, j, v] = find (tril (n));
39 [nr, nc] = size (n);
40 S = sparse (i, j, randn (size (v)), nr, nc);
41 S = S + tril (S, -1)';
42 elseif (nargin == 2)
43 m1 = floor (n/2);
44 n1 = m1 + rem (n, 2);
45 mn1 = m1*n1;
46 k1 = round (d*mn1);
47 idx1 = unique (fix (rand (min (k1*1.01, k1+10), 1) * mn1)) + 1;
48 ## idx contains random numbers in [1,mn] generate 1% or 10 more
49 ## random values than necessary in order to reduce the probability
50 ## that there are less than k distinct values; maybe a better
51 ## strategy could be used but I don't think it's worth the price.
52 37
53 ## Actual number of entries in S. 38 if (nargin != 1 && nargin != 2)
54 k1 = min (length (idx1), k1);
55 j1 = floor ((idx1(1:k1)-1)/m1);
56 i1 = idx1(1:k1) - j1*m1;
57
58 n2 = ceil (n/2);
59 nn2 = n2*n2;
60 k2 = round (d*nn2);
61 idx2 = unique (fix (rand (min (k2*1.01, k1+10), 1) * nn2)) + 1;
62 k2 = min (length (idx2), k2);
63 j2 = floor ((idx2(1:k2)-1)/n2);
64 i2 = idx2(1:k2) - j2*n2;
65
66 if (isempty (i1) && isempty (i2))
67 S = sparse (n, n);
68 else
69 S1 = sparse (i1, j1+1, randn (k1, 1), m1, n1);
70 S = [tril(S1), sparse(m1,m1); ...
71 sparse(i2,j2+1,randn(k2,1),n2,n2), triu(S1,1)'];
72 S = S + tril (S, -1)';
73 endif
74 else
75 print_usage (); 39 print_usage ();
76 endif 40 endif
41
42 if (nargin == 1)
43 [i, j] = find (tril (n));
44 [nr, nc] = size (n);
45 S = sparse (i, j, randn (size (i)), nr, nc);
46 S = S + tril (S, -1)';
47 return;
48 endif
49
50 if (!(isscalar (n) && n == fix (n) && n > 0))
51 error ("sprand: N must be an integer greater than 0");
52 endif
53
54 if (d < 0 || d > 1)
55 error ("sprand: density D must be between 0 and 1");
56 endif
57
58 m1 = floor (n/2);
59 n1 = m1 + rem (n, 2);
60 mn1 = m1*n1;
61 k1 = round (d*mn1);
62 idx1 = unique (fix (rand (min (k1*1.01, k1+10), 1) * mn1)) + 1;
63 ## idx contains random numbers in [1,mn] generate 1% or 10 more
64 ## random values than necessary in order to reduce the probability
65 ## that there are less than k distinct values; maybe a better
66 ## strategy could be used but I don't think it's worth the price.
67
68 ## Actual number of entries in S.
69 k1 = min (length (idx1), k1);
70 j1 = floor ((idx1(1:k1)-1)/m1);
71 i1 = idx1(1:k1) - j1*m1;
72
73 n2 = ceil (n/2);
74 nn2 = n2*n2;
75 k2 = round (d*nn2);
76 idx2 = unique (fix (rand (min (k2*1.01, k1+10), 1) * nn2)) + 1;
77 k2 = min (length (idx2), k2);
78 j2 = floor ((idx2(1:k2)-1)/n2);
79 i2 = idx2(1:k2) - j2*n2;
80
81 if (isempty (i1) && isempty (i2))
82 S = sparse (n, n);
83 else
84 S1 = sparse (i1, j1+1, randn (k1, 1), m1, n1);
85 S = [tril(S1), sparse(m1,m1); ...
86 sparse(i2,j2+1,randn(k2,1),n2,n2), triu(S1,1)'];
87 S = S + tril (S, -1)';
88 endif
89
77 endfunction 90 endfunction
91
92
93 ## FIXME: Test for density can't happen until code of sprandsym is improved
94 %!test
95 %! s = sprandsym (10, 0.1);
96 %! assert (issparse (s));
97 %! assert (issymmetric (s));
98 %! assert (size (s), [10, 10]);
99 ##%! assert (nnz (s) / numel (s), 0.1, .01);
100
101 %% Test 1-input calling form
102 %!test
103 %! s = sprandsym (sparse ([1 2 3], [3 2 3], [2 2 2]));
104 %! [i, j] = find (s);
105 %! assert (sort (i), [2 3]');
106 %! assert (sort (j), [2 3]');
107
108 %% Test input validation
109 %!error sprandsym ()
110 %!error sprandsym (1, 2, 3)
111 %!error sprandsym (ones(3), 0.5)
112 %!error sprandsym (3.5, 0.5)
113 %!error sprandsym (0, 0.5)
114 %!error sprandsym (3, -1)
115 %!error sprandsym (3, 2)
116