New upstream version 1.4.0

1 files changed, 72 insertions, 0 deletions

diff --git a/inst/isShapeMultipart.m b/inst/isShapeMultipart.m
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+++ b/inst/isShapeMultipart.m
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+## Copyright (C) 2016-2020 Philip Nienhuis
+##
+## This program is free software; you can redistribute it and/or modify it
+## under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn {} {@var{mp} =} isShapeMultipart (@var{x}, @var{y})
+## Checks if a polygon or polyline consists of multiple parts separated by
+## NaN rows.
+##
+## @var{x} and @var{y} must be vectors with the same orientation (either
+## row vectors of column vectors).
+##
+## Output argument @var{mp} is zero (false) if the shape contains no NaN
+## rows, otherwise it equals the number of polygon/polyline shape parts.
+##
+## @seealso{}
+## @end deftypefn
+
+## Author: Philip Nienhuis <prnienhuis@users.sf.net>
+## Created: 2016-05-22
+
+function mp = isShapeMultipart (x, y)
+
+  if (nargin  < 2)
+    print_usage ();
+  endif
+  if (isrow (x) != isrow (y))
+    error ("isShapeMultipart: x and y must be both row vectors or both column vectors")
+  endif
+  if (numel (x) != numel (y))
+    error ("isShapeMultipart: incompatible input vectors");
+  endif
+
+  mp = 0;
+  mp_x = find (isnan (x));
+  mp_y = find (isnan (y));
+  if (! isempty (mp_x) && ! isempty (mp_y) && numel (mp_x) == numel (mp_y))
+    if (any (mp_x - mp_y))
+      error ("isShapeMultipart: NaN positions don't match");
+    else
+      mp = numel (mp_x) + 1;
+    endif
+  endif
+
+endfunction
+
+
+%!test
+%! assert (isShapeMultipart ([0 1 0], [1 0 0]), 0);
+
+%!test
+%! h = [0 0 1 NaN 2 2 NaN 3 3];
+%! k = [0 1 0 NaN 2 3 NaN 3 2];
+%! assert (isShapeMultipart (h, k), 3);
+
+%!error <x and y must be both> isShapeMultipart ([0 0 1 NaN 2 2 NaN 3 3], ...
+%!                                               [0 1 0 NaN 2 3 NaN 3 2]')
+%!error <NaN positions don't match> isShapeMultipart ([0 1 NaN 2 3 NaN 4], ...
+%!                                                    [0 1 NaN 2 NaN 3 4])
+%!error <incompatible input> isShapeMultipart ([0 0 1 NaN 2 2 NaN 3 3], ...
+%!                                       [0 1 0 NaN 2 3 NaN 3])