Python3 map() Function

Python3 内置函数Python3 Built-in Functions


Description

The map() function maps the specified sequence according to the provided function.

The first parameter function is called with each element in the parameter sequence, and returns a new list containing the return value of each function call.

Syntax

The following is the syntax of the map() method:

map(function, iterable, ...)

Parameters

  • function -- A function
  • iterable -- One or more sequences

Return Value

Returns an iterator.


Examples

The following examples demonstrate how to use map():

Python3.x Examples

>>> def square(x) :         # Calculate square numbers
...     return x ** 2
...
>>> map(square, [1,2,3,4,5])    # Calculate the square of each element in the list
<map object at 0x100d3d550>     # Returns an iterator
>>> list(map(square, [1,2,3,4,5]))   # Use list() to convert to a list
[1, 4, 9, 16, 25]
>>> list(map(lambda x: x ** 2, [1, 2, 3, 4, 5]))   # Use lambda anonymous function
[1, 4, 9, 16, 25]
>>>

Python3 内置函数Python3 Built-in Functions

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