The filter() API is demonstrated using several examples. In the first example we went through an RDD and output odd numbers by using a lambda expression .filter ( i => (i%2) == 1) which takes advantage of the mod (modulus) function.
In the second example we made it a bit interesting by mapping the result to a square function using a lambda expression num.map(pow(_,2)).filter(_ %2 == 1).
In the third example, we went through the text and filtered out short lines (for example, lines under 30 character) using the lambda expression .filter(_.length < 30).filter(_.length > 0) to print short versus total number of lines (.count() ) as output.
