Index: /issm/trunk-jpl/src/m/morphological/aggregation.m
===================================================================
--- /issm/trunk-jpl/src/m/morphological/aggregation.m	(revision 14579)
+++ /issm/trunk-jpl/src/m/morphological/aggregation.m	(revision 14580)
@@ -1,16 +1,50 @@
-function mask=aggregation(mask,windowsize,threshhold)
-%congrid algorithm using windowsize pixel neighboors.
+function [mask,varargout]=aggregation(mask,windowsize,threshhold,varargin)
+%AGGREGATION - aggregation of an image to a lower sized image
+% 
+%  mask is an image of arbitrary size, format binary, with values 1 for foreground, and 0 for background
+%  mask is first convoluted with a square matrix of size windowsize (where windowsize is an even number), 
+%       it is then filtered according to the threshhold value, and finally subsampled using 1/windowsize as 
+%       sample scaling. 
+%  x,y can be provided as optional arguments, as coordinates of the center points of the mask. aggregation will 
+%       then return subsampled x,y arguments in output.
+% 
+%  Usage:   mask2=aggregation(mask,7,7^2/2);
+%           [mask2,x2,y2]=aggregation(mask,7,7^2,x,y];
+%
+%  See also CLOSING, OPENING, DILATION, EROSION
 
-%check on windowsize
+%check input arguments  %{{{
+%even windowsize
 if mod(windowsize,2)==0,
 	error('windowsize should be an even number');
 end
 
-%convolve: 
+%check on presence of varargin: 
+optional=0;
+if nargin>3,
+	if nargin~=5,
+		help aggregation;
+		error('wrong number of optional arguments specified');
+	else
+		optional=1;
+		x=varargin{1};
+		y=varargin{2};
+	end
+end
+
+%check on presence of varargout: 
+if optional,
+	if nargout~=3,
+		help aggregation;
+		error('wrong number of optional output arguments specified');
+	end
+end
+%}}}
+
+%convolve mask
 matrix=ones(windowsize,windowsize); 
+mask=filter2(matrix,mask,'same');
 
-%convolve mask: 
-mask=filter2(matrix,double(mask),'same');
-
+%apply threshhold
 pos=find(mask>threshhold); 
 pos2=find(mask<=threshhold); 
@@ -18,5 +52,14 @@
 mask(pos2)=0;
 
-%now subsample: 
+%mask has been transformed into double format from the filter2  operation. Bring back to binary. 
+mask=logical(mask);
+
+%subsample: 
 s=size(mask);
 mask=mask(1:windowsize:s(1),1:windowsize:s(2));
+
+if optional,
+	s=size(mask);
+	varargout{1}=x(1:windowsize:s(2));
+	varargout{2}=y(1:windowsize:s(1));
+end
Index: /issm/trunk-jpl/src/m/morphological/nunataks.m
===================================================================
--- /issm/trunk-jpl/src/m/morphological/nunataks.m	(revision 14580)
+++ /issm/trunk-jpl/src/m/morphological/nunataks.m	(revision 14580)
@@ -0,0 +1,70 @@
+function [mask]=nunataks(mask)
+%NUNATAKS - bias mask towards increased 0 covergage
+% 
+%  mask is an image of arbitrary size, format binary, with values 1 for foreground, and 0 for background
+% 
+%  Usage:   mask=nunataks(mask)
+%           [mask]=aggregation(mask);
+%
+%  See also CLOSING, OPENING, DILATION, EROSION, AGGREGATION
+
+%check input arguments  %{{{
+%even windowsize
+if mod(windowsize,2)==0,
+	error('windowsize should be an even number');
+end
+
+%check on presence of varargin: 
+optional=0;
+if nargin>3,
+	if nargin~=5,
+		help aggregation;
+		error('wrong number of optional arguments specified');
+	else
+		optional=1;
+		x=varargin{1};
+		y=varargin{2};
+	end
+end
+
+%check on presence of varargout: 
+if optional,
+	if nargout~=3,
+		help aggregation;
+		error('wrong number of optional output arguments specified');
+	end
+end
+%}}}
+
+%convolve mask
+matrix=ones(windowsize,windowsize); 
+mask=filter2(matrix,mask,'same');
+
+%apply threshhold
+pos=find(mask>threshhold); 
+pos2=find(mask<=threshhold); 
+mask(pos)=1;
+mask(pos2)=0;
+
+%mask has been transformed into double format from the filter2  operation. Bring back to binary. 
+mask=logical(mask);
+
+%subsample: 
+s=size(mask);
+mask=mask(1:windowsize:s(1),1:windowsize:s(2));
+
+if optional,
+	s=size(mask);
+	varargout{1}=x(1:windowsize:s(2));
+	varargout{2}=y(1:windowsize:s(1));
+end
+
+
+function nunataks();
+
+%Bias towards increased rock coverage:
+matrix1=[1 0 1; 0 0 0 ; 1 0 1];
+matrix2=[0 1 0; 1 0 1; 0 1 0];
+
+
+
Index: /issm/trunk-jpl/src/m/morphological/vectorialize.m
===================================================================
--- /issm/trunk-jpl/src/m/morphological/vectorialize.m	(revision 14579)
+++ /issm/trunk-jpl/src/m/morphological/vectorialize.m	(revision 14580)
@@ -1,5 +1,5 @@
 function contours=vectorialize(mask,connectivity);
 
-	vec=bwboundaries(mask,8);
+	vec=bwboundaries(mask,connectivity);
 	
 	contours=struct([]);