Flash cards
Review the key moves
What is the main idea behind Python Numbers?
Lesson checks
Practice each idea before moving on
Short Mimo-style checks built from this lesson's code, terms, and sequence.
Which statement best captures the main point of this lesson?
Complete the missing token from the example code.
y = 2.8 # ___Put the learning moves in the order that makes the concept easiest to apply.
There are three numeric types in Python:
- int
- float
- complex
Variables of numeric types are created when you assign a value to them:
Example
x = 1
# int
y = 2.8 # float
z = 1j # complexTo verify the type of any object in Python, use the type() function:
Example
print(type(x))
print(type(y))
print(type(z))Int
Int, or integer, is a whole number, positive or negative, without decimals, of unlimited length.
Example
x = 1
y = 35656222554887711
z =
-3255522
print(type(x))
print(type(y))
print(type(z))Float
Float, or "floating point number" is a number, positive or negative, containing one or more decimals.
Example
x = 1.10
y = 1.0
z = -35.59
print(type(x))
print(type(y))
print(type(z))Float can also be scientific numbers with an "e" to indicate the power of 10.
Example
x = 35e3
y = 12E4
z = -87.7e100
print(type(x))
print(type(y))
print(type(z))Complex
Complex numbers are written with a "j" as the imaginary part:
Example
x = 3+5j
y = 5j
z = -5j
print(type(x))
print(type(y))
print(type(z))Type Conversion
You can convert from one type to another with the int() , float() , and complex() methods:
Example
x = 1 # int
y = 2.8 # float
z = 1j # complex
#convert from int to float:
a = float(x)
#convert from float to int:
b = int(y)
#convert from int to complex:
c = complex(x)
print(a)
print(b)
print(c)
print(type(a))
print(type(b))
print(type(c))Note
You cannot convert complex numbers into another number type.
Random Number
Python does not have a random() function to make a random number, but Python has a built-in module called random that can be used to make random numbers:
Example
import random
print(random.randrange(1, 10))In our Random Module Reference you will learn more about the Random module.