Print 2 double arrrays, the second one should be cumulative totals of the elements of the first array
About the only thing I would change is this loop

for (x = 0,index2 = 0,index = 0; x &lt; ASIZE; x++, index2++)//adding the second array the elements
{
    cal += array1[index++];
    array2[index2] = cal;
}


You don't need x (its really index1. As all the variables are tracking each other you don't need index2 as index1 is the same value each iteration (and allways do the increment in the for() loop.

The only bug I see is the cal is not initialized to zero and can thus have an indeterminate value.

I would have written it like this:

cal = 0.0;
for (index = 0; index &lt; ASIZE; index++)//adding the second array the elements
{
    cal += array1[index];
    array2[index] = cal;
}


A minor note:

As the code may be changed to have bigger arrays by modifying ASIZE. I would make the user instructions reflect this automaically.

printf("Please enter 8 numbers:\n");

// Try:

printf("Please enter %d numbers:\n", ASIZE);