decring

 function decring(dec, format)

 Draw a ring of constant dec, in 3D

 Inputs:

   dec    - The declination, in radians

   format - A format string for plotting (e.g., 'g' to plot as a green line)

 (EML)

0001 function decring(dec, format)
0002 
0003 % function decring(dec, format)
0004 %
0005 % Draw a ring of constant dec, in 3D
0006 %
0007 % Inputs:
0008 %
0009 %   dec    - The declination, in radians
0010 %
0011 %   format - A format string for plotting (e.g., 'g' to plot as a green line)
0012 %
0013 % (EML)
0014 
0015 t = 0:pi/100:2*pi;
0016 
0017 cd = cos(dec);
0018 sd = sin(dec);
0019 
0020 x = cos(t) * cd;
0021 y = sin(t) * cd;
0022 z = ones(size(t)) * sd;
0023 
0024 plot3(x, y, z, format);
0025 
0026 return
0027 
0028