Pandas dataframe：修订间差异
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（创建页面，内容为“== pandas dataframe conversion == ===dict=== ====dict -> dataframe==== d1 = {"columns":["Apple","Pear"],"data":[[12,0], [8,7], [1, 9]]} df2 = pd.DataFrame(d1['data']) Apple Pear 0 12 0 1 8 7 2 1 9 df2.columns=d1['columns'] Index(['Apple', 'Pear'], dtype='object') ====dataframe -> dict==== Syntax: DataFrame.to_dict(orient=’dict’, into=)\\ Parameters: * orient: String value, (‘dict’, ‘list’, ‘series’, ‘split’…”） |
无编辑摘要 |
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== pandas dataframe conversion == | ===pandas dataframe conversion=== | ||
===dict === | |||
===dict=== | ==== dict -> dataframe==== | ||
====dict -> dataframe==== | d1 = {"columns":["Apple","Pear"],"data":[[12,0], [8,7], [1, 9]]} | ||
d1 = {"columns":["Apple","Pear"],"data":[[12,0], [8,7], [1, 9]]} df2 = pd.DataFrame(d1['data']) | df2 = pd.DataFrame(d1['data']) | ||
Apple Pear | |||
0 12 0 1 8 7 2 1 9 | 0 12 0 | ||
1 8 7 | |||
df2.columns=d1['columns'] Index(['Apple', 'Pear'], dtype='object') | 2 1 9 | ||
df2.columns=d1['columns'] | |||
Index(['Apple', 'Pear'], dtype='object') | |||
====dataframe -> dict==== | ====dataframe -> dict==== | ||
Syntax: DataFrame.to_dict(orient=’dict’, into=) | Syntax: DataFrame.to_dict(orient=’dict’, into=) | ||
Parameters: | Parameters: | ||
* orient: String value, (‘dict’, ‘list’, ‘series’, ‘split’, ‘records’, ‘index’) Defines which dtype to convert Columns(series into). For example, ‘list’ would return a dictionary of lists with Key=Column name and Value=List (Converted series). | |||
* into: class, can pass an actual class or instance. For example in case of defaultdict instance of class can be passed. Default value of this parameter is dict. | |||
====Example==== | ==== Example==== | ||
... df2.to_dict('split') {'index': [0, 1, 2], 'columns': ['Apple', 'Pear'], 'data': [[12, 0], [8, 7], [1, 9]]} | ... | ||
df2.to_dict('split') | |||
df2.to_dict('records') [{'Apple': 12, 'Pear': 0}, {'Apple': 8, 'Pear': 7}, {'Apple': 1, 'Pear': 9}] | {'index': [0, 1, 2], 'columns': ['Apple', 'Pear'], 'data': [[12, 0], [8, 7], [1, 9]]} | ||
df2.to_dict('records') | |||
[{'Apple': 12, 'Pear': 0}, {'Apple': 8, 'Pear': 7}, {'Apple': 1, 'Pear': 9}] | |||
===list=== | ===list=== | ||
====list -> dataframe==== | ====list -> dataframe==== | ||
See also: dict -> dataframe | See also: dict -> dataframe | ||
====dataframe -> list==== | ====dataframe -> list==== | ||
a1 = df1.values # values方法将dataframe转为numpy.ndarray | |||
l1 = a1.tolist() | |||
l1[0] # get frist value | |||
usys.utime(l1[0][7].value/10**9) * P.S. 日期型的字段转换后格式：Timestamp('2017-04-13 13:48:32')，pandas._libs.tslibs.timestamps.Timestamp. 可以使用 usys.utime(l1[0][7].value/10**9) 转换。 | |||
2022年12月28日 (三) 13:10的版本
pandas dataframe conversion
dict
dict -> dataframe
d1 = {"columns":["Apple","Pear"],"data":[[12,0], [8,7], [1, 9]]}
df2 = pd.DataFrame(d1['data'])
Apple Pear
0 12 0
1 8 7
2 1 9
df2.columns=d1['columns']
Index(['Apple', 'Pear'], dtype='object')
dataframe -> dict
Syntax: DataFrame.to_dict(orient=’dict’, into=)
Parameters:
- orient: String value, (‘dict’, ‘list’, ‘series’, ‘split’, ‘records’, ‘index’) Defines which dtype to convert Columns(series into). For example, ‘list’ would return a dictionary of lists with Key=Column name and Value=List (Converted series).
- into: class, can pass an actual class or instance. For example in case of defaultdict instance of class can be passed. Default value of this parameter is dict.
Example
...
df2.to_dict('split')
{'index': [0, 1, 2], 'columns': ['Apple', 'Pear'], 'data': [[12, 0], [8, 7], [1, 9]]}
df2.to_dict('records')
[{'Apple': 12, 'Pear': 0}, {'Apple': 8, 'Pear': 7}, {'Apple': 1, 'Pear': 9}]
list
list -> dataframe
See also: dict -> dataframe
dataframe -> list
a1 = df1.values # values方法将dataframe转为numpy.ndarray
l1 = a1.tolist()
l1[0] # get frist value
usys.utime(l1[0][7].value/10**9) * P.S. 日期型的字段转换后格式：Timestamp('2017-04-13 13:48:32')，pandas._libs.tslibs.timestamps.Timestamp. 可以使用 usys.utime(l1[0][7].value/10**9) 转换。