Python Feature Engineering Cookbook

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With Featuretools, we can also create features at the transaction level or aggregate features at a higher entity level with user-defined operations. Here, we will determine the number of local maxima and minima per customer using Featuretools. Let's get started:

1. To implement user-defined aggregations with Featuretools, we need the make_agg_primitive function and the Numeric object to identify the data type of the variable that this function should be applied to. We also need the find_peaks function to find the local maxima:

from featuretools.primitives import make_agg_primitivefrom featuretools.variable_types import Numericfrom scipy.signal import find_peaks

2. Let's create a function that determines the number of local maxima ...