samer@0: % arrow_sched - Instantiate arrow system to run on background timer and drop into REPL.
samer@0: %
samer@0: % arrow_sched ::
samer@0: %    arrow({},_,_)  ~'arbitrary arrow with no inputs',
samer@0: %    nonneg         ~'period of timer',
samer@0: %    options {
samer@0: %       sched_fig :: handle /0 ~'figure number for scheduler control UI';
samer@0: %       draw      :: boolean /false ~'do drawnow after each iteration';
samer@0: %       exec_mode :: string / 'fixedSpacing' ~'timer execution mode'
samer@0: %    }
samer@0: % -> {...}.
samer@0: %
samer@0: % This function provides a command line with access to a live
samer@0: % system instantiated from the given arrow. The command line
samer@0: % has the prompt 'with_sched>> ' to distinguish it from the normal
samer@0: % Matlab prompt, but in other respects, is the same. The only
samer@0: % commands that function differently are 'quit' and 'exit',
samer@0: % which are trapped and behave as 'return' does, returning control
samer@0: % to this function. Arbitrary values can be returned through to
samer@0: % the called of arrow_repl using ret, eg
samer@0: %   unit>> ret(get_state(),45);  
samer@0: % returns two values: the current state of the system and the
samer@0: % value 45.
samer@0: %
samer@0: % The environment contains the following variables of interest:
samer@0: %    sys  :: arrow(A,B,S).          % the original arrow
samer@0: %    unit :: unit(A,B,S).           % the live processing unit
samer@0: %    sched :: struct.               % scheduler structure (see rsched)
samer@0: %
samer@0: % The following functions are also available:
samer@0: %    get_state  :: () -> S.             % returns the state of the system
samer@0: %    set_state  :: S -> action ().      % sets the state of the system
samer@0: %    stop       :: () -> action ().     % stop processing in timer thread.
samer@0: %    start      :: () -> action ().     % start processing in timer thread.
samer@0: %    startat    :: time -> action ().   % start processing at given time (see nows).
samer@0: %    set_period :: nonneg -> action (). % set period of timer (stops and restarts)
samer@0: %
samer@0: % While running, the background thread calls unit.process() on each
samer@0: % iteration, so the system must have zero inputs. It can have any
samer@0: % number of outputs--these are all discarded while running.
samer@0: 
samer@0: function varargout=arrow_sched(sys,period,varargin)
samer@37: 	opts=options('sched_fig',0,'draw',0,'exec_mode','fixedSpacing','start',0,varargin{:});
samer@0: 	[varargout{1:nargout}]=with_arrow(sys,@with_sched,{},opts,'keyboard',0);
samer@0: 
samer@0: 	function varargout=with_sched(unit)
samer@0: 		if opts.draw, stepfn=@step_draw; else stepfn=@step; end
samer@0: 
samer@0: 		returns={};
samer@0: 		uihandles=[];
samer@0: 		sched=rsched(stepfn,1,period,0,'onstart',@onstart,'onstop',@onstop,'defer',1);
samer@0: 		try
samer@0: 			set(sched.timer(),'ExecutionMode',opts.exec_mode);
samer@0: 			if opts.sched_fig>0
samer@0: 				figure(opts.sched_fig);
samer@0: 				uihandles=sched_ui(sched,12);
samer@0: 			end
samer@0: 
samer@0: 			fprintf('\n');
samer@0: 			if opts.start, 
samer@0: 				fprintf('\nStarting automatically as requested.\n');
samer@0: 				start;
samer@0: 			end
samer@0: 
samer@0: 			fprintf('\nEntering REPL. Type "return","exit", or "quit" to finish.\n');
samer@0: 			fprintf('The function ret(..) sets return values.\n\n');
samer@0: 			cont=true;
samer@0: 			while cont,
samer@0: 				str=input('with_sched>> ','s');
samer@0: 				if strcmp(str,'quit') break; end
samer@0: 				if strcmp(str,'exit') break; end
samer@0: 				if strcmp(str,'return') break; end
samer@0: 				try, eval(str)
samer@0: 				catch ex
samer@0: 					fprintf('\n%s\n',getReport(ex));
samer@0: 				end
samer@0: 			end
samer@0: 		catch ex
samer@0: 			if ~isempty(uihandles), delete(uihandles); end
samer@0: 			if sched.isrunning(), sched.stop(); end
samer@0: 			sched.dispose();
samer@0: 			rethrow(ex);
samer@0: 		end
samer@0: 
samer@0: 		if ~isempty(uihandles), delete(uihandles); end
samer@0: 		if sched.isrunning(), sched.stop(); end
samer@0: 		sched.dispose();
samer@0: 		varargout=returns;
samer@0: 
samer@0: 		function step1
samer@0: 			if sched.isrunning(), error('Already running');
samer@0: 			else
samer@0: 				unit.starting();
samer@0: 				unit.process();
samer@0: 				unit.stopping();
samer@0: 			end
samer@0: 		end
samer@0: 
samer@0: 		function set_period(d)
samer@0: 			if sched.isrunning(), stop; set(sched.timer(),'Period',d); start;
samer@0: 			else set(sched.timer(),'Period',d); end
samer@0: 		end
samer@0: 
samer@0: 		function startat(t), sched.startat(t); end
samer@0: 		function start, sched.start(); end
samer@0: 		function stop, sched.stop(); end
samer@0: 		function set_state(s), unit.set_state(s); end
samer@0: 		function s=get_state, s=unit.get_state(); end
samer@0: 		function onstart(s,t,t0), unit.starting(); end
samer@0: 		function onstop(s,t), unit.stopping(); end
samer@0: 		function ret(varargin), returns=varargin; cont=false; end
samer@0: 		function run_for(its)
samer@0: 			set(sched.timer(),'TasksToExecute',its);
samer@0: 			start;
samer@0: 		end
samer@0: 
samer@0: 		function [s,t0]=step(s,per,t0,dt), 
samer@0: 			unit.process(); 
samer@0: 		end
samer@0: 
samer@0: 		function [s,t0]=step_draw(s,per,t0,dt)
samer@0: 			unit.process();
samer@0: 			drawnow;
samer@0: 		end
samer@0: 	end
samer@0: end