scanLeft and parallel prefix scan as pure lazy transformations #39
Description
An issue for scanLeft and parallell scan for RDDs, as pure lazy transformations:
Implementing an RDD scanLeft Transform With Cascade RDDs
http://erikerlandson.github.io/blog/2014/08/09/implementing-an-rdd-scanleft-transform-with-cascade-rdds/
Implementing Parallel Prefix Scan as a Spark RDD Transform
http://erikerlandson.github.io/blog/2014/08/12/implementing-parallel-prefix-scan-as-a-spark-rdd-transform/