November 2016
Beginner to intermediate
959 pages
43h 46m
English
To demonstrate how MapReduce works, we illustrate the example of a word count, which counts the number of occurrences of each word in a given input set. In this recipe, we will demonstrate how to use rmr2 to implement a word count problem.
In this recipe, we will need an input file as our word count program input. You can download the example input from https://github.com/ywchiu/ml_R_cookbook/tree/master/CH12.
Perform the following steps to implement the word count program:
rmr2 and rhdfs into an R session. You may need to update the use of the JAR file if you use a different version of QuickStart VM:
> Sys.setenv(HADOOP_CMD="/usr/bin/hadoop") ...Read now
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