Index: /issm/trunk-jpl/src/m/boundaryconditions/love_numbers.m
===================================================================
--- /issm/trunk-jpl/src/m/boundaryconditions/love_numbers.m	(revision 21306)
+++ /issm/trunk-jpl/src/m/boundaryconditions/love_numbers.m	(revision 21307)
@@ -4,24 +4,35 @@
 %	in a chosen reference frame 
 %  
-%	Usage: series=love_numbers(type,reference_frame) 
-%	type is one of 'h','k','l','gamma' and 'lambda'. 
-%	reference_frame is one of 'CM' and 'CF'.
+%	Usage: 
+%	series = love_numbers(type) 
+%	series = love_numbers(type,reference_frame) 
+% 
+%	- type = one of 'h','k','l','gamma' and 'lambda'. 
+%	- reference_frame = one of 'CM' (default) and 'CF'.
 %
 %	Example:  
-%	love_k=love_numbers('k','CF');
+%	love_k = love_numbers('k');
+%	love_k = love_numbers('k','CF');
 % 
 
-	%some checks:
-	if nargin~=2, error('love_numbers error message: wrong usage'); end
-
-	if ~( strcmpi(type,'h') | strcmpi(type,'k') | strcmpi(type,'l') | strcmpi(type,'gamma') | strcmpi(type,'lambda') ), 
-		error('type should be one of ''h'',''k'',''l'',''gamma'' and ''lambda''');
-	end
-
+% some checks:
+if nargin==1, 
+	frame='CM'; 
+	disp('Info: computation is done in Center of Mass (CM) reference frame'); 
+elseif nargin==2,
+	frame=reference_frame;
 	if ~( strcmpi(reference_frame,'CM') | strcmpi(reference_frame,'CF')), 
 		error('reference_frame should be one of ''CM'' or ''CF''');
 	end
+else
+	help love_numbers
+	error('bad usage'); 
+end
 
-	love_numbers=[...
+if ~( strcmpi(type,'h') | strcmpi(type,'k') | strcmpi(type,'l') | strcmpi(type,'gamma') | strcmpi(type,'lambda') ), 
+	error('type should be one of ''h'',''k'',''l'',''gamma'' and ''lambda''');
+end
+
+		love_numbers=[...
      0           0          0          0          0          0          0 
 	-1.28740059	-1.00000000	-0.89858519 1.28740059 0.42519882 0.89858519 0.00000000
@@ -10041,7 +10052,7 @@
 
 	% choose degree 1 term for CF reference system 
-	if reference_frame=='CM', 
+	if frame=='CM', 
 		return; 
-	elseif reference_frame=='CF', % from Blewitt, 2003, JGR 
+	elseif frame=='CF', % from Blewitt, 2003, JGR 
 		if type=='h',
 			series(2,1) = -0.269; 
@@ -10052,5 +10063,5 @@
 		end
 	else 
-		error(['love_numbers error message: unknow reference frame:' reference_frame]);
+		error(['love_numbers error message: unknow reference frame:' frame]);
 	end