function [ret,x0,str]=blk_lib(t,x,u,flag);
%BLK_LIB	is the M-file description of the SIMULINK system named BLK_LIB.
%	The block-diagram can be displayed by typing: BLK_LIB.
%
%	SYS=BLK_LIB(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 BLK_LIB 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 BLK_LIB with a FLAG of zero:
%	[SIZES]=BLK_LIB([],[],[],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.
%	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(1.2)
if(0 == (nargin + nargout))
     set_param(sys,'Location',[4,90,159,420])
     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,'/','Input'])
set_param([sys,'/','Input'],...
		'position',[25,60,45,80])

add_block('built-in/Outport',[sys,'/','Output'])
set_param([sys,'/','Output'],...
		'position',[85,60,105,80])

add_block('built-in/Transfer Fcn',[sys,'/','Transfer Fcn'])
set_param([sys,'/','Transfer Fcn'],...
		'Denominator','[1 1]',...
		'position',[50,102,85,138])

add_block('built-in/Zero-Pole',[sys,'/','Zero-Pole'])
set_param([sys,'/','Zero-Pole'],...
		'Poles','[0; -1]',...
		'position',[45,167,90,203])


%     Subsystem  'Simblock'.

new_system([sys,'/','Simblock'])
set_param([sys,'/','Simblock'],'Location',[-10,380,117,533])
set_param([sys,'/','Simblock'],...
		'Mask Display','Return to The Control Kit',...
		'Mask Type','',...
		'Mask Dialogue','eval(''set_param(bname,''''Location'''',[0 0 0 0])'')',...
		'Mask Translate','',...
		'Mask Help','')


%     Finished composite block 'Simblock'.

set_param([sys,'/','Simblock'],...
		'hide name',0,...
		'position',[10,281,135,320])

add_block('built-in/Sum',[sys,'/','Sum'])
set_param([sys,'/','Sum'],...
		'inputs','+-',...
		'position',[25,15,45,35])

add_block('built-in/Integrator',[sys,'/','Integrator'])
set_param([sys,'/','Integrator'],...
		'position',[85,15,105,35])

add_block('built-in/State-space',[sys,'/','State-space'])
set_param([sys,'/','State-space'],...
		'position',[40,230,100,260])

% 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]=',sys,'(t,x,u,flag);'])
		else
			eval(['ret =', sys,'(t,x,u,flag);'])
		end
	else
		[ret,x0,str] = feval(sys);
	end
end