S-function to initialize

This is the s-function that animates a robotic manipulator model; it does't see the vector to initialize the robot graphic (in the function is [0 pi/2 0 0 pi/2 -pi/2 pi]), but it considers only [0 0 0 0 0 0 0].

function [sys,x0,str,ts] = splotbot(t,x,u,flag, robot)
    switch flag,

  case 0
    % initialize the robot graphics
    [sys,x0,str,ts] = mdlInitializeSizes;  % Init
    
        plot(robot, [0 pi/2 0 0 pi/2 -pi/2 pi]);

  case 2
    % come here on update
    if ~isempty(u),
      plot(robot, u');
      drawnow
    end
    ret = [];
  case {1, 4, 9}
    ret = [];
  end
%
%=============================================================================
% mdlInitializeSizes
% Return the sizes, initial conditions, and sample times for the S-function.
%=============================================================================
%
function [sys,x0,str,ts]=mdlInitializeSizes

%
% call simsizes for a sizes structure, fill it in and convert it to a
% sizes array.
%
% Note that in this example, the values are hard coded.  This is not a
% recommended practice as the characteristics of the block are typically
% defined by the S-function parameters.
%
sizes = simsizes;

sizes.NumContStates  = 0;
sizes.NumDiscStates  = 0;
sizes.NumOutputs     = 0;
sizes.NumInputs      = -1;
sizes.DirFeedthrough = 1;
sizes.NumSampleTimes = 1;   % at least one sample time is needed

sys = simsizes(sizes);

%
% initialize the initial conditions
%
x0  = [];

%
% str is always an empty matrix
%
str = [];

%
% initialize the array of sample times
%
ts  = [0 0];

% end mdlInitializeSizes

[Fangjun Jiang]

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