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comparison scripts/geometry/delaunayn.m @ 19172:4318cb91deac

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delaunayn.m: Slight performance increase and addition of BIST tests. * delaunayn.m: Calculate tolerance condition just once rather than every time in loop. Use sumsq rather than sum (x.^2) for another slight performance gain. Add BIST tests.
author Rik <rik@octave.org>
date Sat, 27 Sep 2014 20:36:53 -0700
parents ba167badef9f
children 0e1f5a750d00
comparison
equal deleted inserted replaced
19171:702aa79dc482 19172:4318cb91deac
57 endif 57 endif
58 58
59 T = __delaunayn__ (pts, varargin{:}); 59 T = __delaunayn__ (pts, varargin{:});
60 60
61 if (isa (pts, "single")) 61 if (isa (pts, "single"))
62 myeps = eps ("single"); 62 tol = 1e3 * eps ("single");
63 else 63 else
64 myeps = eps; 64 tol = 1e3 * eps;
65 endif 65 endif
66 66
67 ## Try to remove the zero volume simplices. The volume of the i-th simplex is 67 ## Try to remove the zero volume simplices. The volume of the i-th simplex is
68 ## given by abs(det(pts(T(i,1:end-1),:)-pts(T(i,2:end),:)))/prod(1:n) 68 ## given by abs(det(pts(T(i,1:end-1),:)-pts(T(i,2:end),:)))/prod(1:n)
69 ## (reference http://en.wikipedia.org/wiki/Simplex). Any simplex with a 69 ## (reference http://en.wikipedia.org/wiki/Simplex). Any simplex with a
76 idx = []; 76 idx = [];
77 [nt, n] = size (T); 77 [nt, n] = size (T);
78 ## FIXME: Vectorize this for loop or convert delaunayn to .oct function 78 ## FIXME: Vectorize this for loop or convert delaunayn to .oct function
79 for i = 1:nt 79 for i = 1:nt
80 X = pts(T(i,1:end-1),:) - pts(T(i,2:end),:); 80 X = pts(T(i,1:end-1),:) - pts(T(i,2:end),:);
81 if (abs (det (X)) / sqrt (sum (X .^ 2, 2)) < 1e3 * myeps) 81 if (abs (det (X)) / sqrt (sumsq (X, 2)) < tol)
82 idx(end+1) = i; 82 idx(end+1) = i;
83 endif 83 endif
84 endfor 84 endfor
85 T(idx,:) = []; 85 T(idx,:) = [];
86 86
87 endfunction 87 endfunction
88 88
89 89
90 %!testif HAVE_QHULL
91 %! x = [-1, 0; 0, 1; 1, 0; 0, -1; 0, 0];
92 %! assert (sortrows (sort (delaunayn (x), 2)), [1,2,5;1,4,5;2,3,5;3,4,5]);
93
94 ## Test 3-D input
95 %!testif HAVE_QHULL
96 %! x = [-1, -1, 1, 0, -1]; y = [-1, 1, 1, 0, -1]; z = [0, 0, 0, 1, 1];
97 %! assert (sortrows (sort (delaunayn ([x(:) y(:) z(:)]), 2)), [1,2,3,4;1,2,4,5])
98
90 %% FIXME: Need tests for delaunayn 99 %% FIXME: Need tests for delaunayn
91 100
92 %% FIXME: Need input validation tests 101 %% Input validation tests
102 %!error delaunayn ()
93 103