📝Creating Multiple Objects of a Class

• A very powerful utility of classes is that you can instantiate multiple instances of a class with different attributes.

• This allows you to build scaffolding that supports information, functions, and methods in ways that can be written once and reused.

As you learn more, you can start to appreciate things you have seen before in new ways. Let’s return to the group randomization assignment we did in Lab 1.

1. We start by importing some functions

# import the scientific computing library numpy and give it the nickname np
import numpy as np
import random
import csv

2. Let’s build a class student that contains the information about the students in the class.

# create a python class called Student
class Student:

    # create a constructor for the Student class that has arguments: leader, partners, and name
    def __init__(self, name, number, leader=0, partners=None):

        # stores the name in a data member called self.name

        self.name = name
        self.leader = leader
        self.partners = partners
        self.number = number

    # create a method called _leader
    def _leader(self):

        # increment the value of self.leader by 1
        self.leader += 1

3. We build a class Groups that defines each group in the class.

class Groups:
    def __init__(self, group_number, group_size, group_members, group_leader):
        self.group_number = group_number
        self.group_size = group_size
        self.group_member = group_members
        self.group_leader = group_leader

4. We load a list of Baby Names.

path = "./baby-names-by-state.csv"

# open the file at the specified path for reading and give it the name f
with open(path, "r") as f:
    # create a csv reader object to read the comma-separated file
    reader = csv.reader(f, delimiter=",")
    headers = next(reader)
    data = np.array(list(reader))

names_ = np.unique(data[:, 2])

5. We can now build a list that contains all of the instantiated student objects.

students = []

for i, name in enumerate(names_):
    students.append(Student(name, i))