How to plot graph constant in Matlab?

If I want plot graph same picture ,How to write code.

Answer 1

[Walter Roberson]

function r = Y(x)
  r = zeros(size(x));
  r(x<5) = -10;
  r(x>10) = 15;
end

but now you need to decide what value you want to return if x is exactly 5 or exactly 10. Or at least you do if you want to do this in terms of a function.

If you just need it as a graph and not as a function, then let lowx be the lowest x to plot from, and highx to be the highest x to plot to, and then

plot([lowx 5 5 10 10 highx], [-15 -15 0 0 10 10]);

[Fieldza Field]

Thank you Walter Roberson.I am beginer. I copy code and paste in matlab, but program is error function r = Y(x) | Error: Function definitions are not permitted in this context. How I should ? I'm Sorry,I'm not good english language.