public class GetCdf
extends org.apache.pig.EvalFunc<org.apache.pig.data.Tuple>
This UDF is to get an approximation to the Cumulative Distribution Function (CDF) of the input stream
given a sketch and a set of split points - an array of m unique, monotonically increasing
float values that divide the real number line into m+1 consecutive disjoint intervals.
The function returns an array of m+1 double values, the first m of which are approximations
to the ranks of the corresponding split points (fraction of input stream values that are less than
a split point). The last value is always 1. CDF can also be viewed as a cumulative version of PMF.