public static int mismatch (double[] a, double[] b)

Finds and returns the index of the first mismatch between two double arrays, otherwise return -1 if no mismatch is found. The index will be in the range of 0 (inclusive) up to the length (inclusive) of the smaller array.

If the two arrays share a common prefix then the returned index is the length of the common prefix and it follows that there is a mismatch between the two elements at that index within the respective arrays. If one array is a proper prefix of the other then the returned index is the length of the smaller array and it follows that the index is only valid for the larger array. Otherwise, there is no mismatch.

Two non- null arrays, a and b, share a common prefix of length pl if the following expression is true:

     pl >= 0 &&
     pl < Math.min(a.length, b.length) &&
     Arrays.equals(a, 0, pl, b, 0, pl) &&
     Double.compare(a[pl], b[pl]) != 0
 

Note that a common prefix length of 0 indicates that the first elements from each array mismatch.

Two non- null arrays, a and b, share a proper prefix if the following expression is true:

     a.length != b.length &&
     Arrays.equals(a, 0, Math.min(a.length, b.length),
                   b, 0, Math.min(a.length, b.length))
 

Parameters:

a		the first array to be tested for a mismatch
b		the second array to be tested for a mismatch

Returns:  the index of the first mismatch between the two arrays, otherwise -1.

Exceptions:

NullPointerException

if either array is null

Since:  9