/usr/share/octave/packages/image-2.4.1/imdivide.m is in octave-image 2.4.1-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 | ## Copyright (C) 2011 Carnë Draug <carandraug+dev@gmail.com>
##
## 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 {Function File} {@var{out} =} imdivide (@var{a}, @var{b})
## @deftypefnx {Function File} {@var{out} =} imdivide (@var{a}, @var{b}, @var{class})
## Divide image by another image or constant.
##
## If @var{a} and @var{b} are two images of same size and class, @var{a} is divided
## by @var{b}. Alternatively, if @var{b} is a floating-point scalar, @var{a} is divided
## by it.
##
## The class of @var{out} will be the same as @var{a} unless @var{a} is logical
## in which case @var{out} will be double. Alternatively, it can be
## specified with @var{class}.
##
## @emph{Note}: the values are truncated to the mininum value of the output
## class.
## @seealso{imabsdiff, imadd, imcomplement, immultiply, imlincomb, imsubtract}
## @end deftypefn
function img = imdivide (img, val, out_class = class (img))
if (nargin < 2 || nargin > 3)
print_usage;
endif
[img, val] = imarithmetics ("imdivide", img, val, out_class);
## matlab doesn't even gives a warning in this situation, it simply returns
## a double precision float
if (nargin > 2 && strcmpi (out_class, "logical"))
warning ("Ignoring request to return logical as output of division.");
endif
warning ("off", "Octave:divide-by-zero", "local");
img = img ./ val;
endfunction
%!assert (imdivide (uint8 ([23 250]), uint8 ([ 2 50])), uint8 ([ 12 5])); # default to first class
%!assert (imdivide (uint8 ([56 255]), uint8 ([ 0 0])), uint8 ([255 255])); # dividing by zero works (tested in matlab)
%!assert (imdivide (uint8 ([23 250]), 2), uint8 ([ 12 125])); # works subtracting a scalar
%!assert (imdivide (uint8 ([23 250]), uint8 ([ 2 50]), "uint16"), uint16 ([ 12 5])); # defining output class works (not in matlab)
%!assert (imdivide (logical ([1 1 0 0]), logical ([1 0 1 0])), double ([1 Inf 0 NaN])); # dividing logical matrix (tested in matlab)
%!fail ("imdivide (uint8 ([23 250]), uint16 ([23 250]))"); # input needs to have same class
|