lesson 07 Variables & Data Types · beginner

Whole numbers and decimals

A whole number and a decimal are different values, even when they look similar.

You'll be able to

Store a whole number and print it
Store a decimal and print it
Tell 8 from 8.0 in the console

The idea

A whole number has no decimal point: 8. A decimal has one: 8.0. Python prints them differently, so you can see which kind you stored. A minus sign in front makes a negative number, as in -3. Counts (items, people, days) are usually whole numbers. Money and measurements are usually decimals. Adding and subtracting come in the next module.

Run each example to see what it prints. Running examples doesn't count toward progress.

example-1.py · Two kinds of number

count = 8
price = 8.0
print(count)
print(price)

example-2.py · A price and a refund

price = 43.77
refund = -3
print("Price:", price)
print("Refund:", refund)

Mistake to avoid: the decimal point in Python is a dot, never a comma. price = 12,5 doesn't store twelve and a half. It stores two separate numbers, 12 and 5, and printing it shows (12, 5).

Review

A whole number has no decimal point. A decimal has one, and it is a dot.
Python prints 8 and 8.0 differently.
A minus written against the digits is part of the number. Next: text, True and False.