samer@0: % uiterate - Run a processing unit for some number of iterations
samer@0: %
samer@0: % uiterate :: 
samer@0: %    unit({}, _, _) ~'live processing unit',
samer@0: %    T:natural      ~'number of iterations to run (can be inf)',
samer@0: %    options {
samer@0: %       draw  :: boolean/false ~'whether or not to call drawnow after each iteration';
samer@0: %       quiet :: boolean/false ~'whether or not to suppress progress messages';
samer@0: %       chunk :: natural/1     ~'print progress every chunk interations'
samer@0: %    } 
samer@0: % -> action ().
samer@0: %
samer@0: % This function accepts the live processing unit associated
samer@0: % with an arrow (as created by with_arrow). The arrow must
samer@0: % have zero inputs. Outputs are ignored. If inf iterations are
samer@0: % requested, the system is run until an EOF exception is caught.
samer@0: 
samer@0: function uiterate(u,its,varargin)
samer@0: 	uiter1(u,its,u.process,'label','uiterate',varargin{:});
samer@0: end
samer@0: 
samer@0: function itsdone=uiter1(u,its,itfn,varargin)
samer@37: 	opts=options('draw',1,'quiet',0,'chunk',1,varargin{:});
samer@0: 	quiet=opts.quiet; draw=opts.draw;
samer@0: 	chunk=opts.chunk;
samer@0: 	u.starting();
samer@0: 	try
samer@0: 		i=1;
samer@0: 		while i<=its, 
samer@0: 			if ~quiet && mod(i,chunk)==0, fprintf(' %s: %d   \r',opts.label,i); end
samer@0: 			itfn();
samer@0: 			if draw, drawnow; end
samer@0: 			i=i+1;
samer@0: 		end
samer@0: 	catch ex
samer@0: 		if ~iseof(ex)
samer@0: 			if ~quiet, fprintf('exception at %d iterations.\n',i); end
samer@0: 			u.stopping();
samer@0: 			rethrow(ex); 
samer@0: 		end
samer@0: 	end
samer@0: 	itsdone=i-1;
samer@0: 	if ~quiet, fprintf('done %d iterations.\n',itsdone); end
samer@0: 	u.stopping();
samer@0: end