Mercurial > hg > octave-nkf
diff scripts/general/pol2cart.m @ 10688:7357e37f34fa
coordinate transforms: add option to operate on column matrix of coordinates.
author | Rik <octave@nomad.inbox5.com> |
---|---|
date | Tue, 08 Jun 2010 21:47:05 -0700 |
parents | 742cf6388a8f |
children | be55736a0783 |
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--- a/scripts/general/pol2cart.m +++ b/scripts/general/pol2cart.m @@ -17,13 +17,23 @@ ## <http://www.gnu.org/licenses/>. ## -*- texinfo -*- -## @deftypefn {Function File} {[@var{x}, @var{y}] =} pol2cart (@var{theta}, @var{r}) +## @deftypefn {Function File} {[@var{x}, @var{y}] =} pol2cart (@var{theta}, @var{r}) ## @deftypefnx {Function File} {[@var{x}, @var{y}, @var{z}] =} pol2cart (@var{theta}, @var{r}, @var{z}) +## @deftypefnx {Function File} {[@var{x}, @var{y}] =} pol2cart (@var{p}) +## @deftypefnx {Function File} {[@var{x}, @var{y}, @var{z}] =} pol2cart (@var{p}) +## @deftypefnx {Function File} {@var{C} =} pol2cart (@dots{}) ## Transform polar or cylindrical to Cartesian coordinates. -## @var{theta}, @var{r} (and @var{z}) must be the same shape, or scalar. +## +## @var{theta}, @var{r}, (and @var{z}) must be the same shape, or scalar. ## @var{theta} describes the angle relative to the positive x-axis. ## @var{r} is the distance to the z-axis (0, 0, z). -## @seealso{cart2pol, cart2sph, sph2cart} +## If called with a single matrix argument then each row of @var{p} +## represents the polar/(cylindrical) coordinate (@var{x}, @var{y} (, @var{z})). +## +## If only a single return argument is requested then return a matrix +## @var{C} where each row represents one Cartesian coordinate +## (@var{x}, @var{y} (, @var{z})). +## @seealso{cart2pol, sph2cart, cart2sph} ## @end deftypefn ## Author: Kai Habel <kai.habel@gmx.de> @@ -31,24 +41,41 @@ function [x, y, z] = pol2cart (theta, r, z) - if (nargin < 2 || nargin > 3) - error ("pol2cart: number of arguments must be 2 or 3"); - endif - - if (nargin == 2 && nargout > 2) - error ("pol2cart: number of output arguments must not be greater than number of input arguments"); + if (nargin < 1 || nargin > 3) + print_usage (); endif - if ((ismatrix (theta) && ismatrix (r) && (nargin == 2 || ismatrix (z))) - && (size_equal (theta, r) || isscalar (theta) || isscalar (r)) - && (nargin == 2 || size_equal (theta, z) || isscalar (theta) || isscalar (z)) - && (nargin == 2 || size_equal (r, z) || isscalar (r) || isscalar (z))) + if (nargin == 1) + if (ismatrix (theta) && (columns (theta) == 2 || columns (theta) == 3)) + if (columns (theta) == 3) + z = theta(:,3); + else + z = []; + endif + r = theta(:,2); + theta = theta(:,1); + else + error ("pol2car: matrix input must have 2 or 3 columns [THETA, R (, Z)]"); + endif + elseif (nargin == 2) + if (! ((ismatrix (theta) && ismatrix (r)) + && (size_equal (theta, r) || isscalar (theta) || isscalar (r)))) + error ("pol2cart: arguments must be matrices of same size, or scalar"); + endif + elseif (nargin == 3) + if (! ((ismatrix (theta) && ismatrix (r) && ismatrix (z)) + && (size_equal (theta, r) || isscalar (theta) || isscalar (r)) + && (size_equal (theta, z) || isscalar (theta) || isscalar (z)) + && (size_equal (r, z) || isscalar (r) || isscalar (z)))) + error ("pol2cart: arguments must be matrices of same size, or scalar"); + endif + endif - x = cos (theta) .* r; - y = sin (theta) .* r; + x = r .* cos (theta); + y = r .* sin (theta); - else - error ("pol2cart: arguments must be matrices of same size, or scalar"); + if (nargout <= 1) + x = [x, y, z]; endif endfunction @@ -103,3 +130,13 @@ %! assert (y, [0, 0, 0] / sqrt(2), eps); %! assert (z, z2); +%!test +%! P = [0, 0; pi/4, sqrt(2); pi/4, 2*sqrt(2)]; +%! C = [0, 0; 1, 1; 2, 2]; +%! assert (pol2cart(P), C, sqrt(eps)); + +%!test +%! P = [0, 0, 0; pi/4, sqrt(2), 1; pi/4, 2*sqrt(2), 2]; +%! C = [0, 0, 0; 1, 1, 1; 2, 2, 2]; +%! assert (pol2cart(P), C, sqrt(eps)); +