Using set methods and operators

We have several ways to build a set collection. We can use the set() function to convert an existing collection to a set. We can use the add() method to put items into a set. We can also use the update() method and the union operator, |, to create a larger set from other sets.

We'll show a recipe that uses a set to show whether or not we've seen a complete domain of values from a pool of statistical data. The recipe will build a set collection as the samples are being scanned.

When doing exploratory data analysis, we need to answer the question: Is this data random? Many data collections have variances in the data that are ordinary noise. It's important not to waste time doing complex modeling and analysis of random numbers.

For discrete or continuous numeric data, like the depth of water in meters, or the size of a file in bytes, we can use averages and standard deviations to see if a given collection of data is random. We expect a sample's mean to match the...