diff sequences/@bufferdata/bufferdata.m @ 0:672052bd81f8

Initial partial import.

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sequences/@bufferdata/bufferdata.m	Wed Dec 19 22:38:28 2012 +0000
@@ -0,0 +1,50 @@
+function a=bufferdata(source,L,varargin)
+% bufferdata - collect elements of sequence into sequence of arrays
+%
+% bufferdata :: 
+% 	  data [[N]]	  ~'source signal',
+%	  L:natural	     ~'buffer width',
+%	-> data [[N,L]]. ~'buffered sequence (no-overlapping)'.
+
+
+if nargin==1 && isa(source,'bufferdata'), a=source; 
+elseif nargin==0, a=bufferdata([],1);
+else
+	sz=size1(source);
+	
+	a.dim = length(sz)+1; 
+	a.width = L;
+	[a.buf,source] = readcat(a.dim,source,L); 
+
+	if isempty(a.buf), a=[];
+	else
+		% sort out function table
+		ft.datafn=@datafn;
+		ft.stringfn=@stringfn;
+		ft.nextfn = @nextfn;
+
+		a=class(a,'bufferdata',ddata(source,[sz L],ft));
+	end
+end
+
+function s=stringfn(a), s=sprintf('buffer(%d)',a.width);
+function x=datafn(a), x=a.buf;
+function a=nextfn(a)
+	% read next lot of values and make an array
+	src=source(a);
+	[a.buf,src]=readcat(a.dim,source(a),a.width);
+	if isempty(a.buf), a=[];
+	else
+		a=setsource(a,src);
+		%!! what if i<L?
+		%a.length=size(source(a),a.dim);
+	end
+
+function [buf,src]=readcat(dim,src,L)
+	buf=[];
+	for i=1:L
+		if isempty(src), break; end
+		buf=cat(dim,buf,head(src));
+		src=next(src);
+	end
+