piecewise continuous function in SImulink

Hello!

I made a piecewise functions in Simulink:

function y = fcn(t)
   y = piecewise(t < -1,-1, -1<t<1,0, t > 1,1);

pretty simple, but I got problem with output value of function.

"Simulink cannot determine sizes and/or types of the outputs for block "

How to deal with this problem?

Answer 1

[Ameer Hamza]

piecewise is from symbolic toolbox. It will not work in Simulink. Use if-else block

function y = fcn(t)
    if t < -1
        y = -1;
    elseif t < 1
        y = 0;
    else
        y = 1;
    end

[Mikhail Fedkin]

this was my original function, but this one neither didn't work

function y = sign_with_deadzone (t,delay)
if(t > delay)
  if(t > 0)
      y = 1;
  end
  if(t < 0)
      y = -1;
  end
else
    y = 0;
end

anyway thank you)

[Ameer Hamza]

Is 't' the simulation time? If yes, then it will never be negative and t < 0 will never become true.