angleDiff

ANGLEDIFF Difference between two angles.

   Computes the signed angular difference between two angles in radians.
   The result is comprised between -PI and +PI.

   Example
     A = angleDiff(-pi/4, pi/4)
     A = 
         1.5708    % equal to pi/2
     A = angleDiff(pi/4, -pi/4)
     A = 
        -1.5708    % equal to -pi/2

   See also
   angles2d, angleAbsDiff

 ------
 Author: David Legland
 e-mail: david.legland@grignon.inra.fr
 Created: 2011-07-27,    using Matlab 7.9.0.529 (R2009b)
 Copyright 2011 INRA - Cepia Software Platform.

0001 function dif = angleDiff(angle1, angle2)
0002 %ANGLEDIFF Difference between two angles.
0003 %
0004 %   Computes the signed angular difference between two angles in radians.
0005 %   The result is comprised between -PI and +PI.
0006 %
0007 %   Example
0008 %     A = angleDiff(-pi/4, pi/4)
0009 %     A =
0010 %         1.5708    % equal to pi/2
0011 %     A = angleDiff(pi/4, -pi/4)
0012 %     A =
0013 %        -1.5708    % equal to -pi/2
0014 %
0015 %   See also
0016 %   angles2d, angleAbsDiff
0017 %
0018 % ------
0019 % Author: David Legland
0020 % e-mail: david.legland@grignon.inra.fr
0021 % Created: 2011-07-27,    using Matlab 7.9.0.529 (R2009b)
0022 % Copyright 2011 INRA - Cepia Software Platform.
0023 
0024 % first, normalization
0025 angle1 = normalizeAngle(angle1);
0026 angle2 = normalizeAngle(angle2);
0027 
0028 % compute difference and normalize in [-pi pi]
0029 dif = normalizeAngle(angle2 - angle1, 0);