Mercurial > octave
view scripts/geometry/roty.m @ 33580:80346999b171 bytecode-interpreter tip
build: Fix typo in test/compile/module.mk (bug #65658).
* test/compile/module.mk: Fix typo in path to file.
author | A.R. Burgers <arburgers@gmail.com> |
---|---|
date | Mon, 13 May 2024 11:33:36 +0200 |
parents | 2e484f9f1f18 |
children |
line wrap: on
line source
######################################################################## ## ## Copyright (C) 2019-2024 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{T} =} roty (@var{angle}) ## ## @code{roty} returns the 3x3 transformation matrix corresponding to an active ## rotation of a vector about the y-axis by the specified @var{angle}, given in ## degrees, where a positive angle corresponds to a counterclockwise ## rotation when viewing the z-x plane from the positive y side. ## ## The form of the transformation matrix is: ## @tex ## $$ ## T = \left[\matrix{ \cos(angle) & 0 & \sin(angle) \cr ## 0 & 1 & 0 \cr ## -\sin(angle) & 0 & \cos(angle)}\right]. ## $$ ## @end tex ## @ifnottex ## ## @example ## @group ## | cos(@var{angle}) 0 sin(@var{angle}) | ## T = | 0 1 0 | ## | -sin(@var{angle}) 0 cos(@var{angle}) | ## @end group ## @end example ## @end ifnottex ## ## This rotation matrix is intended to be used as a left-multiplying matrix ## when acting on a column vector, using the notation ## @code{@var{v} = @var{T}*@var{u}}. ## For example, a vector, @var{u}, pointing along the positive z-axis, rotated ## 90-degrees about the y-axis, will result in a vector pointing along the ## positive x-axis: ## ## @example ## @group ## >> u = [0 0 1]' ## u = ## 0 ## 0 ## 1 ## ## >> T = roty (90) ## T = ## 0.00000 0.00000 1.00000 ## 0.00000 1.00000 0.00000 ## -1.00000 0.00000 0.00000 ## ## >> v = T*u ## v = ## 1.00000 ## 0.00000 ## 0.00000 ## @end group ## @end example ## ## @seealso{rotx, rotz} ## @end deftypefn function T = roty (angle) if (nargin < 1 || ! isscalar (angle)) print_usage (); endif angle *= pi / 180; s = sin (angle); c = cos (angle); T = [c 0 s; 0 1 0; -s 0 c]; endfunction ## Function output tests %!assert (roty (0), [1 0 0; 0 1 0; 0 0 1]) %!assert (roty (45), [sqrt(2) 0 sqrt(2); 0 2 0; -sqrt(2) 0 sqrt(2)]./2, 1e-12) %!assert (roty (90), [0 0 1; 0 1 0; -1 0 0], 1e-12) %!assert (roty (180), [-1 0 0; 0 1 0; 0 0 -1], 1e-12) ## Test input validation %!error <Invalid call> roty () %!error <Invalid call> roty ([1 2 3])