Added test for model results not being null before adding the coord_cartesian layer.  This prevents the display of an error message.
Added test for model results not being null before adding the
coord_cartesian layer.  This prevents the display of an error message.

LanceFiondella/srt.core,LanceFiondella/srt.core,arhik/srt.core,LanceFiondella/srt.core,arhik/srt.core,LanceFiondella/srt.core,arhik/srt.core,LanceFiondella/srt.core,LanceFiondella/srt.core,arhik/srt.core