安装padans
cmd>pip3 install pandas
使用
>>> from pandas import Series #一位数组加索引
>>> from pandas import DataFrame #表
>>> obj=Series([1,2,3,4,10])
>>> obj
0 1
1 2
2 3
3 4
4 10
dtype: int64
>>> type(obj)
<class 'pandas.core.series.Series'>
>>> obj.values
array([ 1, 2, 3, 4, 10], dtype=int64)
>>> type(obj.values)
<class 'numpy.ndarray'>
>>> obj.index
RangeIndex(start=0, stop=5, step=1)
>>> obj2=Series([4,7,-5,3],index=[1,2,3,7])
>>> obj2
1 4
2 7
3 -5
7 3
dtype: int64
>>> obj2[1]
4
>>> obj2*2
1 8
2 14
3 -10
7 6
dtype: int64
#处理自动对齐问题
>>> L2=Series([1,3,5,7,9],index=[2,3,4,5,9])
>>> L2
2 1
3 3
4 5
5 7
9 9
dtype: int64
>>> L1+L2
1 NaN
2 3.0
3 7.0
4 10.0
5 NaN
9 NaN
dtype: float64
>>> data = {'1':[1,2,3,4],'2':[5,6,7,8],'3':[9,10,11,12]}
>>> data
{'2': [5, 6, 7, 8], '1': [1, 2, 3, 4], '3': [9, 10, 11, 12]}
>>> F1 =DataFrame(data)
>>> F1
1 2 3
0 1 5 9
1 2 6 10
2 3 7 11
3 4 8 12