如何更改Python字典中条目的键?
当前回答
没有直接的方法做到这一点,但你可以删除然后分配
d = {1:2,3:4}
d[newKey] = d[1]
del d[1]
或者做大量的键改变:
d = dict((changeKey(k), v) for k, v in d.items())
其他回答
你可以使用iff/else字典理解。此方法允许您在一行中替换任意数量的键,并且不需要更改所有键。
key_map_dict = {'a':'apple','c':'cat'}
d = {'a':1,'b':2,'c':3}
d = {(key_map_dict[k] if k in key_map_dict else k):v for (k,v) in d.items() }
返回{“苹果”:1、“b”:2,“猫”:3}
转换字典中的所有键
假设这是你的字典:
>>> sample = {'person-id': '3', 'person-name': 'Bob'}
将示例字典键中的所有破折号转换为下划线:
>>> sample = {key.replace('-', '_'): sample.pop(key) for key in sample.keys()}
>>> sample
>>> {'person_id': '3', 'person_name': 'Bob'}
只需2步即可轻松完成:
dictionary[new_key] = dictionary[old_key]
del dictionary[old_key]
或者一步:
dictionary[new_key] = dictionary.pop(old_key)
如果字典[old_key]未定义,将引发KeyError。注意,这将删除字典[old_key]。
>>> dictionary = { 1: 'one', 2:'two', 3:'three' }
>>> dictionary['ONE'] = dictionary.pop(1)
>>> dictionary
{2: 'two', 3: 'three', 'ONE': 'one'}
>>> dictionary['ONE'] = dictionary.pop(1)
Traceback (most recent call last):
File "<input>", line 1, in <module>
KeyError: 1
我只是要帮我妻子做一些python类的事情,所以我写了这段代码来告诉她如何做。正如标题所示,它只替换键名。这是非常罕见的,你必须替换一个键名,并保持字典的顺序完整,但我还是想分享,因为这篇文章是当你搜索它时谷歌返回的,即使它是一个非常老的线程。
代码:
dictionary = {
"cat": "meow",
"dog": "woof",
"cow": "ding ding ding",
"goat": "beh"
}
def countKeys(dictionary):
num = 0
for key, value in dictionary.items():
num += 1
return num
def keyPosition(dictionary, search):
num = 0
for key, value in dictionary.items():
if key == search:
return num
num += 1
def replaceKey(dictionary, position, newKey):
num = 0
updatedDictionary = {}
for key, value in dictionary.items():
if num == position:
updatedDictionary.update({newKey: value})
else:
updatedDictionary.update({key: value})
num += 1
return updatedDictionary
for x in dictionary:
print("A", x, "goes", dictionary[x])
numKeys = countKeys(dictionary)
print("There are", numKeys, "animals in this list.\n")
print("Woops, that's not what a cow says...")
keyPos = keyPosition(dictionary, "cow")
print("Cow is in the", keyPos, "position, lets put a fox there instead...\n")
dictionary = replaceKey(dictionary, keyPos, "fox")
for x in dictionary:
print("A", x, "goes", dictionary[x])
输出:
A cat goes meow
A dog goes woof
A cow goes ding ding ding
A goat goes beh
There are 4 animals in this list.
Woops, that's not what a cow says...
Cow is in the 2 position, lets put a fox there instead...
A cat goes meow
A dog goes woof
A fox goes ding ding ding
A goat goes beh
完整解决方案的示例
声明一个json文件,其中包含你想要的映射
{
"old_key_name": "new_key_name",
"old_key_name_2": "new_key_name_2",
}
加载它
with open("<filepath>") as json_file:
format_dict = json.load(json_file)
创建此函数来使用映射格式化字典
def format_output(dict_to_format,format_dict):
for row in dict_to_format:
if row in format_dict.keys() and row != format_dict[row]:
dict_to_format[format_dict[row]] = dict_to_format.pop(row)
return dict_to_format
推荐文章
- 证书验证失败:无法获得本地颁发者证书
- 当使用pip3安装包时,“Python中的ssl模块不可用”
- 无法切换Python与pyenv
- Python if not == vs if !=
- 如何从scikit-learn决策树中提取决策规则?
- 为什么在Mac OS X v10.9 (Mavericks)的终端中apt-get功能不起作用?
- 将旋转的xtick标签与各自的xtick对齐
- 为什么元组可以包含可变项?
- 如何合并字典的字典?
- 如何创建类属性?
- 不区分大小写的“in”
- 在Python中获取迭代器中的元素个数
- 解析日期字符串并更改格式
- 使用try和。Python中的if
- 如何在Python中获得所有直接子目录