integrad function not returning an output vector of the same length as the input vector

I have the following function

    function x = rZSum(y, z)
    y = load('delta.txt');
    z = load('aSqr.txt');
    x = y./z;
   format long e
   end

This returns a double workspace variable

I want to integrate this between 0 and 0.9999

I have tried using

    Q = quadl(@rZSum,0,0.9999)

and

     Q = quad(@rZSum,0,0.9999)

with the following error being returned:

    Error using quad (line 75)
    The integrand function must return an output vector of the same length as the input
   vector.

Im unsure of why this error is happening?

Thankyou for any help in advanced!

[Star Strider]

Use trapz or cumtrapz in your application.

[Amy]

 I have tried to use both with the following error being returned:

    Error using diff
    Function 'diff' is not supported for class 'function_handle'.

? Im new to using numerical integration so any help is appreciated thank you