Convert it to a 1D Array, and then use the existing running average tools. You can convert a 2D array to a 1D array using the "Reshape Array" function. You will need to provide this function a "length" argument, which is calculated a the product of the row-length and column-length of your 2D array. The way that I calculate this is to use the "Muliply Array Elements" function on the "size(s)" output of the "Array Size" function (see the attached image file).
