Index: /issm/trunk-jpl/src/m/exp/exp2shp.m
===================================================================
--- /issm/trunk-jpl/src/m/exp/exp2shp.m	(revision 21651)
+++ /issm/trunk-jpl/src/m/exp/exp2shp.m	(revision 21652)
@@ -1,14 +1,25 @@
-function exp2shp(shapefilename,expfilename,geometry)
+function exp2shp(expfilename,shpfilename,geometry)
 %SHPWRITE - write a shape file from a contour structure
 %
 %   Usage:
-%      exp2shp(shapefilename,expfilename,geometry)
+%      exp2shp(expfilename,shpfilename,geometry)
 %
 %   Example:
-%      exp2shp('domainoutline.shp','domainoutline.exp')
-%      exp2shp('domainoutline.shp','domainoutline.exp','Polygon')
-%      exp2shp('massfluxgate.shp','massfluxgate.exp','Line')
+%      exp2shp('domainoutline.exp','domainoutline.shp')
+%      exp2shp('domainoutline.exp','domainoutline.shp','Polygon')
+%      exp2shp('massfluxgate.exp','massfluxgate.shp','Line')
 %
 %   See also SHPREAD, SHPWRITE, SHP2EXP
+
+%check file extensions
+[pathstr,name,ext] = fileparts(shpfilename);
+if ~strcmp(ext,'.shp'),
+	error(['Shapefile ' shpfilename ' does not have an extension .shp']);
+end
+
+[pathstr,name,ext] = fileparts(expfilename);
+if ~strcmp(ext,'.exp'),
+	error(['Exp file ' expfilename ' does not have an extension .exp']);
+end
 
 shp=expread(expfilename);
@@ -34,4 +45,3 @@
 end
 	
-shapewrite(contours,shapefilename);
-end
+shapewrite(contours,shpfilename);