## Copyright (C) 2018 rolf.becker
## 
## 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 2 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 Octave; see the file COPYING.  If not, see
## <http://www.gnu.org/licenses/>.

## turn

## Author: rolf.becker <rolf.becker@hsrw.eu>
## Created: 2018-11-12

function [ ret ] = turn ()
	scl = 0.4;
	lw  = 3;
	sty = 2;
	n   = 16;
	
	Z  = [0 0]';
	P1 = [2 0]';
	P2 = [0 1]';
	M  = 2*[1 1]';

	phi=2*pi/n;
	R=( [cos(phi) -sin(phi) ; sin(phi) cos(phi)] );

	for i=0:n
		arrow(Z,M,scl,sty,lw)
		axis([-5 5 -5 5])
		axis square
		hold on
		arrow(M,M+P1,scl,sty,lw)
		arrow(M,M+P2,scl,sty,lw)
		hold off
		grid on
		set(gca,"fontsize",24,"xtick",-5:5,"ytick",-5:5)
%		title("Rotating Vectors");
		xlabel("x");
		ylabel("y");
		
		M=R*M;
		P1=R*P1;
		P2=R*P2;
		sleep(0.1);
	endfor
endfunction