Python Numbers

There are three numeric types in Python

Python Numbers

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   # complex

    To 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

    Integers:

    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

    Floats:

    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

    Floats:

    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

    Complex:

    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

    Convert from one type to another:

    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 the random module, and display a random number between 1 and 9:

    import random

    print(random.randrange(1, 10))

    In our Random Module Reference you will learn more about the Random module.

    Test Yourself With Exercises

    Exercise:

    Insert the correct syntax to convert x into a floating point number.

    x = 5
    x = (x)
    

    Start the Exercise