map和dict之间的区别 [英] Difference between map and dict

问题描述

我可能会混淆Java中的 hashmap 和 map / dict 。

我认为Java的哈希（k / v抽象）与<$ c相同Python中的$ c> dict

I might be confused between hashmap in Java, and map/dict in Python.
I thought that the hash (k/v abstraction) of Java is kind of the same as dict in Python

但是 map 数据类型有什么作用？

But then what does the map datatype do?

它与哈希图抽象相同吗？如果是这样，那么它与字典有什么不同？

我浏览了文档，但是却把我带到了一起，形成了不同的范例：函数式编程。

Is it the same abstraction as the hashmap abstraction? If so, then how is it different from dictionary?
I went through the docs, but it took me to whole together different paradigm: functional programming.

推荐答案

地图不是数据类型在python中。它将函数应用于一系列值并返回结果。

Map is not a datatype in python. It applies a function to a series of values and returns the result.

>>> def f(x):
...     return x**2
... 
>>> list(map(f, range(5)))
[0, 1, 4, 9, 16]

通常，对于像 pythonic这样的简单情况，我们使用列表推导。

Often for a simple case like that to be "pythonic" we use list comprehensions.

>>> [x**2 for x in range(5)]
[0, 1, 4, 9, 16]

您在比较哈希图和字典时是正确的。

You are right in your comparison of hashmaps and dicts.

这篇关于map和dict之间的区别的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！