Mercurial > octave
view scripts/plot/draw/contourc.m @ 33625:d213a148b3f1 default tip @
ensure exp. terminal widget has focus at startup
* main-window.cc (main_window): call focus_command_window only if
event loop is idle by using a single shot timer
* main-window.h: make focus_command_window a public slot
author | Torsten Lilge <ttl-octave@mailbox.org> |
---|---|
date | Sun, 26 May 2024 02:29:44 +0200 |
parents | 2e484f9f1f18 |
children |
line wrap: on
line source
######################################################################## ## ## Copyright (C) 2003-2024 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{c} =} contourc (@var{z}) ## @deftypefnx {} {@var{c} =} contourc (@var{z}, @var{vn}) ## @deftypefnx {} {@var{c} =} contourc (@var{x}, @var{y}, @var{z}) ## @deftypefnx {} {@var{c} =} contourc (@var{x}, @var{y}, @var{z}, @var{vn}) ## @deftypefnx {} {[@var{c}, @var{lev}] =} contourc (@dots{}) ## Compute contour lines (isolines of constant Z value). ## ## The matrix @var{z} contains height values above the rectangular grid ## determined by @var{x} and @var{y}. If only a single input @var{z} is ## provided then @var{x} is taken to be @code{1:columns (@var{z})} and @var{y} ## is taken to be @code{1:rows (@var{z})}. The minimum data size is 2x2. ## ## The optional input @var{vn} is either a scalar denoting the number of ## contour lines to compute or a vector containing the Z values where lines ## will be computed. When @var{vn} is a vector the number of contour lines ## is @code{numel (@var{vn})}. However, to compute a single contour line ## at a given value use @code{@var{vn} = [val, val]}. If @var{vn} is omitted ## it defaults to 10. ## ## The return value @var{c} is a 2x@var{n} matrix containing the contour lines ## in the following format ## ## @example ## @group ## @var{c} = [lev1, x1, x2, @dots{}, levn, x1, x2, ... ## len1, y1, y2, @dots{}, lenn, y1, y2, @dots{}] ## @end group ## @end example ## ## @noindent ## in which contour line @var{n} has a level (height) of @var{levn} and length ## of @var{lenn}. ## ## The optional return value @var{lev} is a vector with the Z values of the ## contour levels. ## ## Example: ## ## @example ## @group ## x = 0:2; ## y = x; ## z = x' * y; ## c = contourc (x, y, z, 2:3) ## @result{} c = ## 2.0000 1.0000 1.0000 2.0000 2.0000 3.0000 1.5000 2.0000 ## 4.0000 2.0000 2.0000 1.0000 1.0000 2.0000 2.0000 1.5000 ## @end group ## @end example ## @seealso{contour, contourf, contour3, clabel} ## @end deftypefn function [c, lev] = contourc (varargin) if (nargin < 1 || nargin > 4) print_usage (); endif if (nargin == 1) z = varargin{1}; x = 1:columns (z); y = 1:rows (z); vn = 10; elseif (nargin == 2) z = varargin{1}; x = 1:columns (z); y = 1:rows (z); vn = varargin{2}; elseif (nargin == 3) x = varargin{1}; y = varargin{2}; z = varargin{3}; vn = 10; elseif (nargin == 4) x = varargin{1}; y = varargin{2}; z = varargin{3}; vn = varargin{4}; endif if (! (isnumeric (z) && isnumeric (x) && isnumeric (y)) || ! (ismatrix (z) && ismatrix (x) && ismatrix (y)) || ! (isreal (z) && isreal (x) && isreal (y))) error ("contourc: X, Y, and Z must be real numeric matrices"); endif if (rows (z) < 2 || columns (z) < 2) error ("contourc: Z data must have at least 2 rows and 2 columns"); endif if (isscalar (vn)) lev = linspace (min (z(:)), max (z(:)), vn+2)(2:end-1); else lev = unique (sort (vn)); endif if (isvector (x) && isvector (y)) c = __contourc__ (x(:)', y(:)', z, lev); elseif (! any (bsxfun (@minus, x, x(1,:))(:)) && ! any (bsxfun (@minus, y, y(:,1))(:))) ## x,y are uniform grid (such as from meshgrid) c = __contourc__ (x(1,:), y(:,1)', z, lev); else ## Data is sampled over non-uniform mesh. ## Algorithm calculates contours for uniform grid ## and then interpolates values back to the non-uniform mesh. ## Uniform grid for __contourc__. [nr, nc] = size (z); ii = 1:nc; jj = 1:nr; c = __contourc__ (ii, jj, z, lev); ## Map the contour lines from index space (i,j) ## back to the original grid (x,y) i = 1; while (i < columns (c)) clen = c(2, i); idx = i + (1:clen); ci = c(1, idx); cj = c(2, idx); ## Due to rounding errors, some elements of ci and cj can fall out of the ## range of ii and jj and interp2 would return NA for those values. ## The permitted range is enforced here: ci = max (ci, 1); ci = min (ci, nc); cj = max (cj, 1); cj = min (cj, nr); c(1, idx) = interp2 (ii, jj, x, ci, cj); c(2, idx) = interp2 (ii, jj, y, ci, cj); i += (clen + 1); endwhile endif endfunction %!test %! x = 0:2; %! y = x; %! z = x' * y; %! c_exp = [2, 1, 1, 2, 2, 3, 1.5, 2; 4, 2, 2, 1, 1, 2, 2, 1.5]; %! lev_exp = [2 3]; %! [c_obs, lev_obs] = contourc (x, y, z, 2:3); %! assert (c_obs, c_exp, eps); %! assert (lev_obs, lev_exp, eps); ## Test input validation %!error <Invalid call> contourc () %!error <Invalid call> contourc (1,2,3,4,5) %!error <X, Y, and Z must be .* numeric> contourc ({3}) %!error <X, Y, and Z must be .* numeric> contourc ({1}, 2, 3) %!error <X, Y, and Z must be .* numeric> contourc (1, {2}, 3) %!error <X, Y, and Z must be .* matrices> contourc (ones (3,3,3)) %!error <X, Y, and Z must be .* matrices> contourc (ones (3,3,3), 2, 3) %!error <X, Y, and Z must be .* matrices> contourc (1, ones (3,3,3), 3) %!error <X, Y, and Z must be real> contourc (3i) %!error <X, Y, and Z must be real> contourc (1i, 2, 3) %!error <X, Y, and Z must be real> contourc (1, 2i, 3) %!error <Z data must have at least 2 rows> contourc ([1, 2]) %!error <Z data must have at least .* 2 columns> contourc ([1; 2])