Plot piecewise function on an interval

I'm trying to plot the above periodic function on the interval -10 < t < 10

I can plot it once using:

pw = evalin(symengine,'piecewise([t > -2 and t <= 0, -t^2],[t >=0 and t < 2, t^2])');
fplot(pw)

How would I plot this function on the interval?

Answer 1

[Torsten]

function y=f(t)
   y = zeros(size(t)); % Preallocating enough memory for y

   tmod=mod(t,4)-2;

   region1 = (tmod<0) & (tmod>=-2); % First interval
   y(region1) = -tmod(region1).^2;

   region2 = (tmod>=0) & (tmod<=2); % Second interval
   y(region2) = tmod(region2).^2;

Now you can do this:

   t = -10:0.1:10;
   y = f(t);
   plot(t, y)

Best wishes

Torsten.

[Torsten]

I think it should read

tmod = mod(t+2,4)-2;

instead of

tmod = mod(t,4)-2;

Best wishes

Torsten.