I am going through the lab exercise 10.3 Analyze Flight Delays with Spark Machine Learning Scenario under chapter 10 for Machine learning.
My question is from Page 147 Lab Guide for
My question is what does the green highlighted section do in the below code snippet.
//Below we transform non-numeric features into numeric values. For example, the carrier AA is the number 6.
var carrierMap: Map[String, Int] = Map()