Category Archives : Programming


Pyspark Joins by Example

Summary: Pyspark DataFrames have a join method which takes three parameters: DataFrame on the right side of the join, Which fields are being joined on, and what type of join (inner, outer, left_outer, right_outer, leftsemi). You call the join method from the left side DataFrame object such as df1.join(df2, df1.col1 == df2.col1, ‘inner’).

Pyspark Join Data with Two Tables (A and B)

Pyspark ALS and Recommendation Outputs

Lately, I’ve written a few iterations of pyspark to develop a recommender system (I’ve had some practice creating recommender systems in pyspark). I ran into a situation where I needed to generate some recommendations on some different datasets. My problem was that I had to decipher some of the prediction documentation. Because of my struggles, […]


Writing Quality Data Mining Code

Summary: Writing better quality data mining code requires you to write code that is self-explanatory and does one thing at a time well. In terms of analysis, you should be cross-validating and watching for slowly changing relationships in the data.

Split Your Code Apart!