sugr_angle_Line_2D

% Get angle between two 2D lines 

 angle = sugr_angle_Line_2D(l,m)

 * l, m   2D line, struct {l.h,l.Crr}

 * angle.a  = angle between lines, from l to m in [0,2*pi)%
        .sa = standard deviation angle negativ if one line is infinte%
        .dof = degrees of freedom = 1

 Wolfgang Förstner 2/2011
 wfoerstn@uni-bonn.de 

 See also sugr_Line_2D

0001 %% Get angle between two 2D lines
0002 %
0003 % angle = sugr_angle_Line_2D(l,m)
0004 %
0005 % * l, m   2D line, struct {l.h,l.Crr}
0006 %
0007 % * angle.a  = angle between lines, from l to m in [0,2*pi)%
0008 %        .sa = standard deviation angle negativ if one line is infinte%
0009 %        .dof = degrees of freedom = 1
0010 %
0011 % Wolfgang Förstner 2/2011
0012 % wfoerstn@uni-bonn.de
0013 %
0014 % See also sugr_Line_2D
0015 
0016 function angle = sugr_angle_Line_2D(l,m)
0017 
0018 
0019 if sugr_get_isfinite_Line_2D(l) && sugr_get_isfinite_Line_2D(m)
0020 
0021     % Hessean parameters of l and m
0022     [le, Clee] = sugr_get_Euclidean_Line_2D(l);
0023     [me, Cmee] = sugr_get_Euclidean_Line_2D(m);
0024 
0025     % angle and standard deviation
0026     angle.a = mod(me(1) - le(1),2*pi);
0027     angle.sa = sqrt(Clee(1,1) + Cmee(1,1));
0028 
0029 else        % one line at infinity
0030     angle.a = 0;
0031     angle.sa = -1;
0032 end
0033 angle.dof = 1;
0034 
0035 
0036 
0037 
0038 
0039 
0040