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16.2: Type Conversion Functions

  • Page ID
    15363
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    Python provides built-in functions that convert values from one type to another. The int function takes any value and converts it to an integer, if it can, or complains otherwise:

    >>> int('32')
    32
    >>> int('Hello')
    ValueError: invalid literal for int(): Hello
    

    int can convert floating-point values to integers, but it doesn’t round off; it chops off the fraction part:

    >>> int(3.99999)
    3
    >>> int(-2.3)
    -2
    

    float converts integers and strings to floating-point numbers:

    >>> float(32)
    32.0
    >>> float('3.14159')
    3.14159
    

    Finally, str converts its argument to a string:

    >>> str(32)
    '32'
    >>> str(3.14159)
    '3.14159'

    This page titled 16.2: Type Conversion Functions is shared under a CC BY-NC-SA 3.0 license and was authored, remixed, and/or curated by Allen B. Downey (Green Tea Press) .

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