Integrating a multivariable function defined with logical operation

I have defined a multivariable function in Matlab as:

    function f=test(x,y)

    if x>=0 && y>0
        f=x+y;
    end

    if x<0 && y>0
     f=-x+y;
    end

    end

Now I want to integrate the function over x but with y fixed to be 1, so in the command window I wrote:

    f=@(x) test(x,1);
    integrate(f,-1,1)

Then I got an error saying:

    Operands to the || and && operators must be convertible to logical scalar values.

    Error in test (line 3)
    if x>=0 && y>0

If I replace all && by & with everything else unchanged, there is another error:

    Output argument "f" (and maybe others) not assigned during call to "test".

    Error in @(x)test(x,1)

I appreciate if someone can help me do this integral numerically.

By the way, I noticed the problems appearing here seem to be unique when in the definition of the function there is some logical operation. If I defined

    function f=test(x,y)
        f=x+y;
    end

and do the integral as before

    f=@(x) test(x,1);
    integral(f,-1,1)

It correctly returns 2.

Answer 1

[Andrei Bobrov]

function f=test(x,y)
    if x>=0 && y>0
        f=x+y;
    end
    if x<0 && y>0
     f=-x+y;
    end
end

>>f=@(x) test(x,1);
>>integral(f,-1,1,'ArrayValued',true)