Index: /issm/trunk/src/m/classes/public/plot/applyoptions.m
===================================================================
--- /issm/trunk/src/m/classes/public/plot/applyoptions.m	(revision 2871)
+++ /issm/trunk/src/m/classes/public/plot/applyoptions.m	(revision 2872)
@@ -90,4 +90,7 @@
 	if exist(options,'log'),
 		logvalue=getfieldvalue(options,'log');
+		if any(getfieldvalue(options,'caxis')<=0),
+			error('applyoptions error message: negative log values when trying to apply caxis option');
+		end
 		caxis(log(getfieldvalue(options,'caxis'))/log(logvalue));
 	else