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Python Introduction to Data Visualization with Matplotlib Chart Toppers Scatter Plot

Anshul Laikar
Anshul Laikar
4,428 Points
Posted by Anshul Laikar
Anshul Laikar
4,428 Points

What does groupby do exactly?

I read the itertools thing on python's website. It says that groupby basically divides the list whenever the iterator changes values. But what then? Where does it store these groups? How exactly does it iterate? I did not really understand that.

Anshul Laikar
Anshul Laikar
4,428 Points
Anshul Laikar
Anshul Laikar
4,428 Points

I was messing around with the iterator and came by this:

from itertools import groupby
import csv
import matplotlib.pyplot as plt
input_file = 'iris.csv'

with open(input_file, 'r') as iris_data:
    irises = list(csv.reader(iris_data))

colors = {"Iris-setosa": "#2B5B84", "Iris-versicolor": "g", "Iris-virginica": "purple"}
irises.pop()
i=0
for group in groupby(irises, lambda i: i[4]):
    cat_ir= list(group)
    print(cat_ir)
    print(species)
    print(i)

    i+=1

I haven't mentioned species anywhere in the given program or named it as a variable. How does print(species) still work?

1 Answer

Gaurav Sharma
Gaurav Sharma
5,496 Points
Gaurav Sharma
Gaurav Sharma
5,496 Points

okay, that's interesting. Have you found its answer yet?