ungerboe.m

数字通信第四版原书的例程

function [ret,x0,str,ts,xts]=ungerboe(t,x,u,flag);
%UNGERBOE	is the M-file description of the SIMULINK system named UNGERBOE.
%	The block-diagram can be displayed by typing: UNGERBOE.
%
%	SYS=UNGERBOE(T,X,U,FLAG) returns depending on FLAG certain
%	system values given time point, T, current state vector, X,
%	and input vector, U.
%	FLAG is used to indicate the type of output to be returned in SYS.
%
%	Setting FLAG=1 causes UNGERBOE to return state derivatives, FLAG=2
%	discrete states, FLAG=3 system outputs and FLAG=4 next sample
%	time. For more information and other options see SFUNC.
%
%	Calling UNGERBOE with a FLAG of zero:
%	[SIZES]=UNGERBOE([],[],[],0),  returns a vector, SIZES, which
%	contains the sizes of the state vector and other parameters.
%		SIZES(1) number of states
%		SIZES(2) number of discrete states
%		SIZES(3) number of outputs
%		SIZES(4) number of inputs
%		SIZES(5) number of roots (currently unsupported)
%		SIZES(6) direct feedthrough flag
%		SIZES(7) number of sample times
%
%	For the definition of other parameters in SIZES, see SFUNC.
%	See also, TRIM, LINMOD, LINSIM, EULER, RK23, RK45, ADAMS, GEAR.

% Note: This M-file is only used for saving graphical information;
%       after the model is loaded into memory an internal model
%       representation is used.

% the system will take on the name of this mfile:
sys = mfilename;
new_system(sys)
simver(1.3)
if (0 == (nargin + nargout))
     set_param(sys,'Location',[110,42,581,172])
     open_system(sys)
end;
set_param(sys,'algorithm',     'RK-45')
set_param(sys,'Start time',    '0.0')
set_param(sys,'Stop time',     '999999')
set_param(sys,'Min step size', '0.0001')
set_param(sys,'Max step size', '10')
set_param(sys,'Relative error','1e-3')
set_param(sys,'Return vars',   '')

add_block('built-in/Inport',[sys,'/','In1'])
set_param([sys,'/','In1'],...
		'position',[35,35,55,55])

add_block('built-in/Outport',[sys,'/','Out1'])
set_param([sys,'/','Out1'],...
		'position',[425,30,445,50])

add_block('built-in/Outport',[sys,'/','Out2'])
set_param([sys,'/','Out2'],...
		'Port','2',...
		'position',[425,80,445,100])

add_block('built-in/Logical Operator',[sys,'/',['Logical',13,'Operator']])
set_param([sys,'/',['Logical',13,'Operator']],...
		'ForeGround',4,...
		'hide name',0,...
		'Operator','XOR',...
		'position',[320,22,365,53])

add_block('built-in/Memory',[sys,'/','Memory'])
set_param([sys,'/','Memory'],...
		'ForeGround',2,...
		'hide name',0,...
		'position',[215,30,255,60])

add_block('built-in/Memory',[sys,'/','Memory1'])
set_param([sys,'/','Memory1'],...
		'ForeGround',2,...
		'hide name',0,...
		'position',[115,30,155,60])
add_line(sys,[60,45;110,45])
add_line(sys,[160,45;210,45])
add_line(sys,[260,45;315,45])
add_line(sys,[75,45;75,20;290,20;290,30;315,30])
add_line(sys,[370,40;420,40])
add_line(sys,[180,45;180,90;420,90])

drawnow

% Return any arguments.
if (nargin | nargout)
	% Must use feval here to access system in memory
	if (nargin > 3)
		if (flag == 0)
			eval(['[ret,x0,str,ts,xts]=',sys,'(t,x,u,flag);'])
		else
			eval(['ret =', sys,'(t,x,u,flag);'])
		end
	else
		[ret,x0,str,ts,xts] = feval(sys);
	end
else
	drawnow % Flash up the model and execute load callback
end