How to write an 'if' script that changes a function depending on x?

Hello!

I am trying to write a script that changes a function depending on the value of x.

sin(x) if x<=3

arctan(x) if 3<x<=7

e^-x if x<7

trying to only use 1 if statement!

function y=funk(x)
    if
    x <= 3;
    y=sin(x);
    else
    (3<x) && (x>=7);
    y=atan(x);
    else 
    x>7;
    y=e^(-x)
    end

I'm not sure if i made a syntax error or the code is just plain wrong... Any help is appriciated!

Answer 1

[Johan]

you need to use elseif for secondary condition in your if statement:

function y=funk(x)
    if
        x <= 3;
        y=sin(x);
    elseif
        (3<x) && (x>=7);
        y=atan(x);
    else 
        x>7;
        y=e^(-x)
    end

[Luqas Lundahl]

would i need to use else if on the second else as well?

Answer 2

[Torsten]

function y = funk(x)
  if x <= 3
    y = sin(x);
  elseif (x > 3) && (x <= 7)
    y = atan(x);
  else
    y = exp(-x);
  end
end

[Luqas Lundahl]

thank you!