Introduction to Python basics-Python Tutorial-php.cn

Introduction to Python basics

巴扎黑

Release： 2017-07-22 13:21:25

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特殊的数据类型

>>> list1 = [1, &#39;wang&#39;, &#39;tao&#39;]
>>> tuple1 = (2, &#39;wang&#39;, &#39;tao&#39;, &#39;yuan&#39;)    #tuple的内容不可更改
>>> dict1 = {			           #dict的元素分为 key:value两部分，key不能重复
	&#39;wang&#39;:90,
	&#39;tao&#39;:99,
	&#39;yuan&#39;:100
	}

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dict 的用法，转自

OperationResultNoteslen(a)the number of items in a 得到字典中元素的个数 a[k]the item of a with key k 取得键K所对应的值(1), (10)a[k] = vset a[k] to v 设定键k所对应的值成为v del a[k]remove a[k] from a 从字典中删除键为k的元素(1)a.clear()remove all items from a 清空整个字典 a.copy()a (shallow) copy of a 得到字典副本 k in aTrue if a has a key k, else False 字典中存在键k则为返回True，没有则返回False(2)k not in aEquivalent to not k in a 字典中不存在键k则为返回true,反之返回False(2)a.has_key(k)Equivalent to k in a, use that form in new code 等价于k in a a.items()a copy of a's list of (key, value) pairs 得到一个键，值的list(3)a.keys()a copy of a's list of keys 得到键的list(3)a.update([b])updates (and overwrites) key/value pairs from b从b字典中更新a字典，如果键相同则更新，a中不存在则追加(9)a.fromkeys(seq[, value])Creates a new dictionary with keys from seq and values set to value (7)a.values()a copy of a's list of values(3)a.get(k[, x])a[k] if k in a, else x(4)a.setdefault(k[, x])a[k] if k in a, else x (also setting it)(5)a.pop(k[, x])a[k] if k in a, else x (and remove k)(8)a.popitem()remove and return an arbitrary (key, value) pair(6)a.iteritems()return an iterator over (key, value) pairs(2), (3)a.iterkeys()return an iterator over the mapping's keys(2), (3)a.itervalues()return an iterator over the mapping's values(2), (3)

set ([ , ])相当于dict的key组成的列表，具有元素不可重复的特点

特殊操作

定义函数 def f( ): f为函数名,注意后面要加冒号

增加操作 append() 追加到list尾部

extend()将列表b加到a后

insert(1, 'g')

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