Lecture 11 — Lists

Overview

  • So far we’ve looked at working with individual values and variables.

  • We realized that this is cumbersome and so we started working with iterables like Tuples.

  • This is a way to aggregate multiple values and refer to them using a single variable.

  • With Lists we will get acquainted with an extremely flexible iterable object type in Python.

  • Unlike tuples or strings, Lists are mutable as we will learn.

This lecture is largely based on Sections 8.1-8.3 of Practical Programming.

Lists are Sequences of Values

  • Put together values that have common meaning.

  • As a first example, here are scores of 10 students for a test:

    scores = [95, 78, 63, 63, 68, 84, 88, 93, 71, 80]

  • As a second example, here are the names of the planets in the solar system:

    planet_names = ['Mercury', 'Venus', 'Earth', 'Mras', 'Jupiter',
    'Saturn', 'Neptune', 'Uranus']

  • Notes on syntax:

    • Begin with [ and end with ].

    • Commas separate the individual values.

    • The spaces between values are optional and are used for clarity here.

    • Any type of object may be stored in a list, and each list can mix different types.