SPARK URL's

http://spark.apache.org/docs/latest/programming-guide.html

http://www.openkb.info/2015/01/scala-on-spark-cheatsheet.html

https://www.linkedin.com/pulse/spark-mapreduce-scala-underscore-vishnu-viswanath

val lines = sc.parallelize(List("a b", "c d","e f","g h","i j","k l"))

val firstwords = lines.map(line => (line.substring(0,line.indexOf(" ")))).collect()

http://ampcamp.berkeley.edu/wp-content/uploads/2013/02/Parallel-Programming-With-Spark-Matei-Zaharia-Strata-2013.pdf

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