本文详细介绍Python中列表、元组和字典的基本操作方法，包括创建、增删改查等核心功能，并提供具体实例帮助理解。
目录
一、列表
Python默认库中的“list”类提供了11种对列表的操作方式
class list(object):
"""
list() -> new empty list
list(iterable) -> new list initialized from iterable's items
"""
def append(self, p_object): # real signature unknown; restored from __doc__
""" L.append(object) -> None -- append object to end """
""" 在列表末尾新增一个元素 """
pass
def clear(self): # real signature unknown; restored from __doc__
""" L.clear() -> None -- remove all items from L """
""" 清空列表 """
pass
def copy(self): # real signature unknown; restored from __doc__
""" L.copy() -> list -- a shallow copy of L """
""" 将列表浅复制一份 """
return []
def count(self, value): # real signature unknown; restored from __doc__
""" L.count(value) -> integer -- return number of occurrences of value """
""" 返回列表中元素出现的次数 """
return 0
def extend(self, iterable): # real signature unknown; restored from __doc__
""" L.extend(iterable) -> None -- extend list by appending elements from the iterable """
""" 将列表进行扩展，实参为另一个列表 """
pass
def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__
"""
L.index(value, [start, [stop]]) -> integer -- return first index of value.
Raises ValueError if the value is not present.
"""
""" 返回列表值的索引，如果存在多个元素，取第一个元素的索引 """
return 0
def insert(self, index, p_object): # real signature unknown; restored from __doc__
""" L.insert(index, object) -- insert object before index """
""" 在传入值的前面插入一个元素 """
pass
def pop(self, index=None): # real signature unknown; restored from __doc__
"""
L.pop([index]) -> item -- remove and return item at index (default last).
Raises IndexError if list is empty or index is out of range.
"""
""" 删除列表中的一个元素，如果未指定参数，默认删除最后一项 """
pass
def remove(self, value): # real signature unknown; restored from __doc__
"""
L.remove(value) -> None -- remove first occurrence of value.
Raises ValueError if the value is not present.
"""
""" 删除列表中一个元素，如果列表中存在多个元素，则删除第一个 """
pass
def reverse(self): # real signature unknown; restored from __doc__
""" L.reverse() -- reverse *IN PLACE* """
""" 反转 """
pass
def sort(self, key=None, reverse=False): # real signature unknown; restored from __doc__
""" L.sort(key=None, reverse=False) -> None -- stable sort *IN PLACE* """
""" 排序，Python3支持不同类型的排序，排序规则为：特殊字符、数字、大写、小写 """
pass1.0、创建列表
name = ["fixzhang","man","Love","World",24,"BiBi"]
a = ["I","Love","U"]
b = ["0","7","21"]
c = ["This",["is","copy"]]1.1、append
>>name = ["fixzhang", "man", "Love", "World", 24, "BiBi"]
>>name.append("GAGA")
>>print(name)
['fixzhang', 'man', 'Love', 'World', 24, 'BiBi', 'GAGA']1.2、clear
>>name = ["fixzhang", "man", "Love", "World", 24, "BiBi"]
>>print(name)
['fixzhang', 'man', 'Love', 'World', 24, 'BiBi']
>>name.clear()
>>print(name)
[]1.3、copy
>>c = ["This", ["is", "copy"]]
>>d = c.copy()
>>print(d)
['This', ['is', 'copy']]1.4、count
>>name = ["fixzhang", "man", "Love", "World", 24, "BiBi", "man"]
>>print(name.count("man"))
21.5、extend
方法一：
>>a = ["I", "Love", "U"]
>>b = ["0", "7", "21"]
>>a.extend(b)
>>print(a)
['I', 'Love', 'U', '0', '7', '21']方法二：
>>name = ["fixzhang", "man", "Love", "World", 24, "BiBi"]
>>a = ["I", "Love", "U"]
>>b = ["0", "7", "21"]
>>a += b
>>print(a)
['I', 'Love', 'U', '0', '7', '21']1.6、index
>>name = ["fixzhang", "man", "Love", "World", 24, "BiBi", "man"]
>>print(name.index("Love"))
21.7、insert
>>name = ["fixzhang", "man", "Love", "World", 24, "BiBi"]
>>name.insert(1, "HaHa")
>>print(name)
['fixzhang', 'HaHa', 'man', 'Love', 'World', 24, 'BiBi']1.8、pop
>>name = ["fixzhang", "man", "Love", "World", 24, "BiBi"]
>>name.pop(-2)
>>print(name)
['fixzhang', 'man', 'Love', 'World', 'BiBi']1.9、remove
>>name = ["fixzhang", "man", "Love", "World", 24, "BiBi", "man"]
>>name.remove("man")
>>print(name)
['fixzhang', 'Love', 'World', 24, 'BiBi', 'man']1.10、reverse
>>name = ["fixzhang", "man", "Love", "World", "24", "BiBi"]
>>name.reverse()
>>print(name)
['BiBi', '24', 'World', 'Love', 'man', 'fixzhang']1.11、sort
>>name = ["fixzhang", "man", "Love", "World", "24", "BiBi"]
>>name.sort()
>>print(name)
['24', 'BiBi', 'Love', 'World', 'fixzhang', 'man']1.12、切片
# 取下标1至下标4之间的元素，包括1，不包括4
>>name = ["fixzhang", "man", "Love", "World", 24, "BiBi"]
>>print(name[1:4])
['man', 'Love', 'World']
-------------------------------------------------------------
# 从头开始取，或者到结尾，0可以忽略，结尾要想包含必须只能填
>>name = ["fixzhang", "man", "Love", "World", 24, "BiBi"]
>>print(name[:])
['fixzhang', 'man', 'Love', 'World', 24, 'BiBi']
-------------------------------------------------------------
# 根据步长取值，从左往右，步长为2取元素
>>name = ["fixzhang", "man", "Love", "World", 24, "BiBi"]
>>print(name[::2])
['fixzhang', 'Love', 24]
-------------------------------------------------------------
# 根据步长取值，从右往左，步长为2取元素
>>name = ["fixzhang", "man", "Love", "World", 24, "BiBi"]
>>print(name[::-2])
['BiBi', 'World', 'man']二、元组
元组其实跟列表差不多，也是存一组数，只不是它一旦创建，便不能再修改，所以又叫只读列表。Python默认库中的“tuple”类提供了3种对列表的操作方式。
class tuple(object):
"""
tuple() -> empty tuple
tuple(iterable) -> tuple initialized from iterable's items
If the argument is a tuple, the return value is the same object.
"""
def count(self, value): # real signature unknown; restored from __doc__
""" T.count(value) -> integer -- return number of occurrences of value """
""" 返回列表中元素出现的次数 """
return 0
def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__
"""
T.index(value, [start, [stop]]) -> integer -- return first index of value.
Raises ValueError if the value is not present.
"""
""" 返回列表值的索引，如果存在多个元素，取第一个元素的索引 """
return 02.0、创建元组
name = ("fix zhang","man","Love","World",24,"BiBi")2.1、count
>>name = ("fix zhang", "man", "Love", "World", 24, "BiBi")
>>print(name.count("man"))
12.2、index
>>name = ("fix zhang", "man", "Love", "World", 24, "BiBi")
>>print(name.index("man"))
1三、字典
字典一种key - value 的数据类型，使用就像我们上学用的字典，通过笔划、字母来查对应页的详细内容。
特点：
- 无序
- Key是唯一的，所以天生去重
class dict(object):
"""
dict() -> new empty dictionary
dict(mapping) -> new dictionary initialized from a mapping object's
(key, value) pairs
dict(iterable) -> new dictionary initialized as if via:
d = {}
for k, v in iterable:
d[k] = v
dict(**kwargs) -> new dictionary initialized with the name=value pairs
in the keyword argument list. For example: dict(one=1, two=2)
"""
def clear(self): # real signature unknown; restored from __doc__
""" D.clear() -> None. Remove all items from D. """
pass
def copy(self): # real signature unknown; restored from __doc__
""" D.copy() -> a shallow copy of D """
pass
@staticmethod # known case
def fromkeys(*args, **kwargs): # real signature unknown
""" Returns a new dict with keys from iterable and values equal to value. """
pass
def get(self, k, d=None): # real signature unknown; restored from __doc__
""" D.get(k[,d]) -> D[k] if k in D, else d. d defaults to None. """
pass
def items(self): # real signature unknown; restored from __doc__
""" D.items() -> a set-like object providing a view on D's items """
pass
def keys(self): # real signature unknown; restored from __doc__
""" D.keys() -> a set-like object providing a view on D's keys """
pass
def pop(self, k, d=None): # real signature unknown; restored from __doc__
"""
D.pop(k[,d]) -> v, remove specified key and return the corresponding value.
If key is not found, d is returned if given, otherwise KeyError is raised
"""
pass
def popitem(self): # real signature unknown; restored from __doc__
"""
D.popitem() -> (k, v), remove and return some (key, value) pair as a
2-tuple; but raise KeyError if D is empty.
"""
pass
def setdefault(self, k, d=None): # real signature unknown; restored from __doc__
""" D.setdefault(k[,d]) -> D.get(k,d), also set D[k]=d if k not in D """
pass
def update(self, E=None, **F): # known special case of dict.update
"""
D.update([E, ]**F) -> None. Update D from dict/iterable E and F.
If E is present and has a .keys() method, then does: for k in E: D[k] = E[k]
If E is present and lacks a .keys() method, then does: for k, v in E: D[k] = v
In either case, this is followed by: for k in F: D[k] = F[k]
"""
pass
def values(self): # real signature unknown; restored from __doc__
""" D.values() -> an object providing a view on D's values """
pass3.0、创建字典
3.1、clear
>>info = {
"stu1101":"zhang san",
"stu1102":"li si",
"stu1103":"xiao ming",
}
>>info.clear()
>>print(info)
{}3.2、copy
>>info = {
"stu1101":"zhang san",
"stu1102":"li si",
"stu1103":"xiao ming",
}
>>aa = info.copy()
>>print(aa)
{'stu1101': 'zhang san', 'stu1102': 'li si', 'stu1103': 'xiao ming'}3.3、fromkeys
>>info = {
"stu1101": "zhang san",
"stu1102": "li si",
"stu1103": "xiao ming",
}
>>print(info.fromkeys("stu1103", "hello"))
{'s': 'hello', 't': 'hello', 'u': 'hello', '1': 'hello', '0': 'hello', '3': 'hello'}3.4、get
>>info = {
"stu1101": "zhang san",
"stu1102": "li si",
"stu1103": "xiao ming",
}
>>print(info.get("stu1101"))
zhang san
>>print(info.get("stu1104"))
None3.5、items
>>info = {
"stu1101": "zhang san",
"stu1102": "li si",
"stu1103": "xiao ming",
}
>>print(info.items())
dict_items([('stu1101', 'zhang san'), ('stu1102', 'li si'), ('stu1103', 'xiao ming')])3.6、keys
>>info = {
"stu1101": "zhang san",
"stu1102": "li si",
"stu1103": "xiao ming",
}
>>print(info.keys())
dict_keys(['stu1101', 'stu1102', 'stu1103'])3.7、pop
>>info = {
"stu1101": "zhang san",
"stu1102": "li si",
"stu1103": "xiao ming",
}
>>info.pop("stu1101")
>>print(info)
{'stu1102': 'li si', 'stu1103': 'xiao ming'}也可以使用“del”来删除
>>info = {
"stu1101":"zhang san",
"stu1102":"li si",
"stu1103":"xiao ming",
}
>>del info["stu1101"]
>>print(info)
{'stu1102': 'li si', 'stu1103': 'xiao ming'}3.8、popitem
>>info = {
"stu1101":"zhang san",
"stu1102":"li si",
"stu1103":"xiao ming",
}
>>info.popitem()
>>print(info)
{'stu1101': 'zhang san', 'stu1102': 'li si'}3.9、setdefault
>>info = {
"stu1101": "zhang san",
"stu1102": "li si",
"stu1103": "xiao ming",
}
>>info.setdefault("stu1104", "wang wu")
>>print(info)
{'stu1101': 'zhang san', 'stu1102': 'li si', 'stu1103': 'xiao ming', 'stu1104': 'wang wu'}
--------------------------------------------------------------------------------
>>info.setdefault("stu1103", "wang wu")
>>print(info)
{'stu1101': 'zhang san', 'stu1102': 'li si', 'stu1103': 'xiao ming'}3.10、update
>>info = {
"stu1101": "zhang san",
"stu1102": "li si",
"stu1103": "xiao ming",
}
>>info2 = {
"1": "zhang san",
"stu1103": "小明",
}
>>info.update(info2)
>>print(info)
{'stu1101': 'zhang san', 'stu1102': 'li si', 'stu1103': '小明', '1': 'zhang san'}3.11、values
>>info = {
"stu1101": "zhang san",
"stu1102": "li si",
"stu1103": "xiao ming",
}
>>print(info.values())
dict_values(['zhang san', 'li si', 'xiao ming'])
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