[pol] = SensorToPolar
Converts from sensor rectangular coordinates to polar
Polar coordinates are defined as radius, azimuth, and elevation.
See also PolarToSensor
9/9/93 jms It didn't work for matrix inputs, because a
matrix '^' needed to be a by-element '.^'
9/26/93 dhb Added calData argument.
2/6/94 jms Changed 'polar' to 'pol'
2/20/94 jms Added single argument case to avoid cData
4/6/96 dhb Fixed bug noted by ccc. Need to use four quadrant
5/20/98 dhb Fix little bug, make sure index is not empty.
4/5/02 dhb, ly New calling interface.
11/6/06 dhb Only allow one input argument.
2/10/07 dhb Finish above fix.