Over a million developers have joined DZone.

A JavaScript MapReduce One-Liner

· Big Data Zone

Learn how you can maximize big data in the cloud with Apache Hadoop. Download this eBook now. Brought to you in partnership with Hortonworks.

After my post on "Word frequency using MapReduce in Python," I got my paws dirty with some silly Javascript. Once I reduced a whole chunk of code, it turned out to be a simple one-liner in JavaScript. A linear implementation of MapReduce, but it was fun and indeed will be useful if on node.js.

Enough talking! Below is the one liner that will give the word frequency in JSON format.

One-liner:

String.prototype.map_reduce = function(){return this.toLowerCase().split(/\W+/g).reduce(function (t, w) { if (w) t[w] = (t[w] || 0) + 1; return t; }, {}).toSource()}

The prettier version:

String.prototype.map_reduce = function () {
return this.toLowerCase().
split(/\W+/g).
reduce(function (t, w) {
if (w) {
t[w] = (t[w] || 0) + 1;
}
return t;
}, {}).
toSource()
}

Example :

>>> "The quick brown fox jumped over the lazy".map_reduce()

>>> "({the:2, quick:1, brown:1, fox:1, jumped:1, over:1, lazy:1, dog:1})"

 

Hortonworks DataFlow is an integrated platform that makes data ingestion fast, easy, and secure. Download the white paper now.  Brought to you in partnership with Hortonworks

Topics:

Published at DZone with permission of Hemanth HM, DZone MVB. See the original article here.

Opinions expressed by DZone contributors are their own.

The best of DZone straight to your inbox.

SEE AN EXAMPLE
Please provide a valid email address.

Thanks for subscribing!

Awesome! Check your inbox to verify your email so you can start receiving the latest in tech news and resources.
Subscribe

{{ parent.title || parent.header.title}}

{{ parent.tldr }}

{{ parent.urlSource.name }}