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2.2: Variables

  • Page ID
    8536
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    One of the most powerful features of a programming language is the ability to manipulate variables. A variable is a name that refers to a value.

    An assignment statement creates new variables and gives them values:

    >>> message = 'And now for something completely different'
    >>> n = 17
    >>> pi = 3.1415926535897931

    This example makes three assignments. The first assigns a string to a new variable named message; the second assigns the integer 17 to n; the third assigns the (approximate) value of π to pi.

    To display the value of a variable, you can use a print statement:

    >>> print(n)
    17
    >>> print(pi)
    3.141592653589793

    The type of a variable is the type of the value it refers to.

    >>> type(message)
    <class 'str'>
    >>> type(n)
    <class 'int'>
    >>> type(pi)
    <class 'float'>

    This page titled 2.2: Variables is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by Chuck Severance.

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