Mercurial > octave
view scripts/general/rescale.m @ 31248:8b75954a4670
delaunayn: adjust node ordering for positive outward normal vectors (bug #53397)
* delaunayn.m: Check sign of simplex volume, flip node order for negative
volumes to ensure positive (outward-pointing) normal vectors. Add BISTs to
check for positive volumes.
* etc/News.8.md: Append function improvement note to delaunayn change
paragraph under General Improvements.
author | Nicholas R. Jankowski <jankowski.nicholas@gmail.com> |
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date | Thu, 29 Sep 2022 23:09:05 -0400 |
parents | 796f54d4ddbf |
children | 597f3ee61a48 |
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######################################################################## ## ## Copyright (C) 2019-2022 The Octave Project Developers ## ## See the file COPYRIGHT.md in the top-level directory of this ## distribution or <https://octave.org/copyright/>. ## ## This file is part of Octave. ## ## Octave 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. ## ## Octave 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 Octave; see the file COPYING. If not, see ## <https://www.gnu.org/licenses/>. ## ######################################################################## ## -*- texinfo -*- ## @deftypefn {} {@var{B} =} rescale (@var{A}) ## @deftypefnx {} {@var{B} =} rescale (@var{A}, @var{l}, @var{u}) ## @deftypefnx {} {@var{B} =} rescale (@dots{}, "inputmin", @var{inmin}) ## @deftypefnx {} {@var{B} =} rescale (@dots{}, "inputmax", @var{inmax}) ## Scale matrix elements to a specified range of values. ## ## When called with a single matrix argument @var{A}, rescale elements to ## occupy the interval [0, 1]. ## ## The optional inputs @code{[@var{l}, @var{u}]} will scale @var{A} to the ## interval with lower bound @var{l} and upper bound @var{u}. ## ## The optional input @qcode{"inputmin"} replaces all elements less than ## the specified value @var{inmin} with @var{inmin}. Similarly, the optional ## input @qcode{"inputmax"} replaces all elements greater than the specified ## value @var{inmax} with @var{inmax}. If unspecified the minimum and maximum ## are taken from the data itself (@w{@code{@var{inmin} = min (A(:))}} and ## @w{@code{@var{inmax} = max (A(:))}}). ## ## Programming Notes: ## The applied formula is ## ## @tex ## $$B = l + {A - inmin \over inmax - inmin} \cdot (u - l)$$ ## @end tex ## @ifnottex ## @var{B} = @var{l} + ((@var{A} - @var{inmin}) ./ (@var{inmax} - @var{inmin})) ## .* (@var{u} - @var{l}) ## @end ifnottex ## ## The class of the output matrix @var{B} is single if the input @var{A} is ## single, but otherwise is of class double for inputs which are of double, ## integer, or logical type. ## ## @seealso{bounds, min, max} ## @end deftypefn function B = rescale (A, varargin) if (! any (nargin == [1,3,5,7])) print_usage (); endif ## Verify A input. if (! (isnumeric (A) || islogical (A))) error ("rescale: A must be a numeric or logical matrix"); endif ## Use class double for integers and logical types if (! isa (A, "single")) A = double (A); endif l = 0; u = 1; ## If 2nd and 3rd argument are numeric, set non-default interval [l, u]. if (nargin > 1 && isnumeric (varargin{1})) if (! isnumeric (varargin{2})) error ("rescale: upper bound U must be numeric"); endif l = varargin{1}; u = varargin{2}; varargin(1:2) = []; if (any ((l > u)(:))) error ("rescale: lower bound L must be smaller than upper bound U"); endif ## FIXME: Need input validation for cases where l or u is not a scalar endif truncate_range = false; ## Check for named argument "inputmin". inminidx = find (strcmpi (varargin, "inputmin"), 1, "last"); if (! isempty (inminidx)) if (! isnumeric (varargin{inminidx + 1})) error ("rescale: INMIN must be numeric"); endif inmin = varargin{inminidx + 1}; varargin(inminidx:inminidx + 1) = []; truncate_range = true; else inmin = min (A(:)); endif ## Check for named argument "inputmax". inmaxidx = find (strcmpi (varargin, "inputmax"), 1, "last"); if (! isempty (inmaxidx)) if (! isnumeric (varargin{inmaxidx + 1})) error ("rescale: INMAX must be numeric"); endif inmax = varargin{inmaxidx + 1}; varargin(inmaxidx:inmaxidx + 1) = []; truncate_range = true; else inmax = max (A(:)); endif ## Verify all options were processed if (! isempty (varargin)) error ("rescale: invalid option(s)"); endif ## Rescale A to interval [l,u] in range interval [inmin, inmax]. range = inmax - inmin; range(range == 0) = 1; # Avoid division by 0 resulting in NaN B = l + (A - inmin) ./ range .* (u - l); if (truncate_range) B(A < inmin) = l; B(A > inmax) = u; endif endfunction %!assert (rescale ([]), []) %!assert (rescale ([0]), [0]) %!assert (rescale ([1]), [0]) %!assert (rescale (0:5), (0:5)/5) ## Test [l,u] input %!assert (rescale (1:4, 3, 9), [3,5,7,9]) %!test %! A = repmat ([1:3]', [1, 3]); %! B = rescale (A, [1, 2, 3], 5); %! assert (B, [1, 2, 3; 3, 3.5, 4; 5, 5, 5]); %!test %! A = repmat ([1:3]', [1, 3]); %! B = rescale (A, [1; 2; 3], 5); %! assert (B, [1, 1, 1; 3.5, 3.5, 3.5; 5, 5, 5]); ## Test property/value options %!assert (rescale (0:6, "inputmin", 1, "inputmax", 5), [0,0,0.25,0.5,0.75,1,1]) ## Test class of returned output %!assert (class (rescale (single ([0, 5]))), "single") %!assert (class (rescale (double ([0, 5]))), "double") %!assert (class (rescale (int8 ([0, 5]))), "double") %!assert (class (rescale (logical ([0, 1]))), "double") ## Test input validation %!error <Invalid call> rescale () %!error <Invalid call> rescale (1, 2) %!error <Invalid call> rescale (1, 2, 3, 4) %!error <Invalid call> rescale (1, 2, 3, 4, 5, 6) %!error <Invalid call> rescale (1, 2, 3, 4, 5, 6, 7, 8) %!error <A must be a numeric or logical matrix> rescale ("abc") %!error <A must be a numeric or logical matrix> rescale ({ [1] }) %!error <U must be numeric> rescale (1, 0, "A") %!error <L must be smaller than .* U> rescale (1, 2, 0) ## FIXME: Need BIST tests here when input validation has been added for ## l and u not being scalar. %!error <INMIN must be numeric> rescale (1, "inputmin", "abc") %!error <INMAX must be numeric> rescale (1, "inputmax", "abc") %!error <invalid option> rescale (1, "foobar", 1)