Python Machine Learning Blueprints - Second Edition

map

We'll now begin with the map function. The map function works on series, so in our case we will use it to transform a column of our DataFrame, which you will recall is just a pandas series. Suppose we decide that the species numbers are not suitable for our needs. We'll use the map function with a Python dictionary as the argument to accomplish this. We'll pass in a replacement for each of the unique iris types:

Let's look at what we have done here. We have run the map function over each of the values of the existing species column. As each value was found in the Python dictionary, it was added to the return series. We assigned this return ...