1. A computer implemented method for identifying a cluster of data points, the method comprising: mapping each of the data points into a bitmap by, for each data point, initially setting a bit in the bitmap that corresponds to that data point on the computer; and applying a plurality of expansion shapes to the initially set bits on the computer, wherein each of said plurality of expansion shapes is applied in a one to one correspondence to each of the initially set bits, wherein said applying an expansion shape includes setting each of the bits within the expansion shape.