How its possible do define this function in Matlab?

Hello everyone! Im new to Matlab and i have a little problem.

I have tried to define this function like this:

function F = func(t)
  time = t>=0 && t<1;  F(time) = t+1;
  time = t>=1 && t<2;  F(time) = 0;
  time = t>=2 && t<3;  F(time) = 2-t;
  time = t>=3;         F(time) = 0;
end

But, it gives me error(picture below):

Can you help me, please

Answer 1

[Jan]

Your funcion is almost correct. Just change && to & and consider the logical index time in the output.

The problem in your case was a symbolic input. The function requires a numerical input:

func(linspace(0, 4, 20))

ans = 1×20

1.0000 1.2105 1.4211 1.6316 1.8421 0 0 0 0 0 -0.1053 -0.3158 -0.5263 -0.7368 -0.9474 0 0 0 0 0

function F = func(t)
  time = t>=0 & t<1;  F(time) = t(time) + 1;
  time = t>=1 & t<2;  F(time) = 0;
  time = t>=2 & t<3;  F(time) = 2 - t(time);
  time = t>=3;        F(time) = 0;
end

A slight simplification:

function F = func(t)
  F = zeros(size(t));  % Pre-allocation
  time    = (t>=0 & t<1);
  F(time) = t(time) + 1;
  time    = (t>=2 & t<3);
  F(time) = 2 - t(time);
end

Answer 2

[KSSV]

function g = func(t)
if t >=0 && t < 1
    g = t+1 ;
elseif t >= 1 && t < 2
    g = 0 ;
elseif t >= 2 && t < 3
    g = 2-t ;
elseif t >= 3
    g = 0 ;
end

Save the above and call it as:

g = func(0) ; 

Your function should be:

function F = func(t)
  time = t>=0 & t<1;  F(time) = t(time)+1;
  time = t>=1 & t<2;  F(time) = 0;
  time = t>=2 & t<3;  F(time) = 2-t(time);
  time = t>=3;        F(time) = 0;
end