Calculates the entropy of any old input range of observations more quickly
* than entropy(), provided that all equal values are adjacent. If the input
* is sorted by more than one key, i.e. structs, the result will be the joint
* entropy of all of the keys. The compFun alias will be used to compare
* adjacent elements and determine how many instances of each value exist.
Calculates the entropy of any old input range of observations more quickly * than entropy(), provided that all equal values are adjacent. If the input * is sorted by more than one key, i.e. structs, the result will be the joint * entropy of all of the keys. The compFun alias will be used to compare * adjacent elements and determine how many instances of each value exist.