Answers for "is there a simple mthod that sums all elements in an array"

javascript get elements that exist in two arrays

function getArraysIntersection(a1,a2){
    return  a1.filter(function(n) { return a2.indexOf(n) !== -1;});
}
var colors1 = ["red","blue","green"];
var colors2 = ["red","yellow","blue"];
var intersectingColors=getArraysIntersection(colors1, colors2); //["red", "blue"]

Return a new RDD containing only the elements that satisfy a predicate.

rdd = sc.parallelize([1, 2, 3, 4, 5])
rdd.filter(lambda x: x % 2 == 0).collect()
# [2, 4]