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8.1: A list is a sequence

  • Page ID
    3132
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    Like a string, a list is a sequence of values. In a string, the values are characters; in a list, they can be any type. The values in list are called elements or sometimes items.

    There are several ways to create a new list; the simplest is to enclose the elements in square brackets ([ and ]):

    [10, 20, 30, 40]
    ['crunchy frog', 'ram bladder', 'lark vomit']

    The first example is a list of four integers. The second is a list of three strings. The elements of a list don't have to be the same type. The following list contains a string, a float, an integer, and (lo!) another list:

    ['spam', 2.0, 5, [10, 20]]

    A list within another list is nested.

    A list that contains no elements is called an empty list; you can create one with empty brackets, [].

    As you might expect, you can assign list values to variables:

    >>> cheeses = ['Cheddar', 'Edam', 'Gouda']
    >>> numbers = [17, 123]
    >>> empty = []
    >>> print(cheeses, numbers, empty)
    ['Cheddar', 'Edam', 'Gouda'] [17, 123] []

    This page titled 8.1: A list is a sequence is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Chuck Severance via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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