Practical Data Analysis Cookbook

Using regular expressions and GREL to clean up data

When cleaning up and preparing data for use, we sometimes need to extract some information from text fields. Occasionally, we can just split the text fields using delimiters. However, when a pattern of data does not allow us to simply split the text, we need to revert to regular expressions.

Getting ready

To follow this recipe, you need to have OpenRefine and virtually any Internet browser installed on your computer.

We assume that you followed the previous recipes and your data is already loaded to OpenRefine and the data types are now representative of what the columns hold. No other prerequisites are required.

How to do it…

First, let's have a look at the pattern that occurs in our city_state_zip ...