ences the output to the track coordinate
% nearest to the location given by a two-element vector |[reflat reflon]|.  This might be 
% useful when analyzing distance along a satellite ground track relative to a point of 
% interest such as a grounding line. 
% 
% |d = pathdistps(...,'ref',[refx refy])| references the output as above, but using polar
% stereogprahic (ps71) coordinates. 
% 
% |d = pathdistps(...,'FixDistortion',false)| calculates distances in pure polar stereographic 
% coordinates without acc