if elseif end error

hi i got some error during use matlab

function [r,theta] = matlab36
x = [2 2 0 -3 -2 -1 0 0 2];
y = [0 1 3 1 0 -2 0 -2 2];
r = sqrt((x.^2)+(y.^2));
if x>0
    theta = atan(y./x);
end
if x<0
    if y>0
        theta = atan(y./x)+pi;
    elseif y<0
        theta = atan(y./x)-pi;
    elseif y==0
        theta = pi;
    end
end

if x==0
    if y>0
        theta = pi/2;
    elseif y<0
        theta = -pi/2;
    elseif y==0
        theta = 0;
    end
end

the answer says there is no any substitution value 'theta' i don't know how can i fix this error

Answer 1

[Manan Mishra]

I was not able to reproduce the same error on my end. However the issue could be because the output theta is not being assigned during the function call.

This is because none of the if-statements under which theta is assigned are being executed.

Please note that for a vector x, the condition x>0 will return true only if all the elements of x are greater than 0.