机器学习pandas数据结构之Panel笔记

 1 import numpy as np
 2 import pandas as pd
 3 
 4 data = {‘Item1‘:pd.DataFrame(np.random.randn(4,3)),
 5         ‘Item2‘:pd.DataFrame(np.random.randn(4,2))}
 6 
 7 pn = pd.Panel(data)  # 创建Panel
 8 pn
 9 # 输出
10 <class ‘pandas.core.panel.Panel‘>
11 Dimensions: 2 (items) x 4 (major_axis) x 3 (minor_axis)
12 Items axis: Item1 to Item2
13 Major_axis axis: 0 to 3
14 Minor_axis axis: 0 to 2
15 
16 pn[‘Item1‘]
17 #输出的是DataFrame
18 
19 pn.items
20 # 输出Index([‘Item1‘, ‘Item2‘], dtype=‘object‘)
21 
22 pn.major_axis
23 # 输出 RangeIndex(start=0, stop=4, step=1)
24 
25 pn.minor_axis
26 # 输出 RangeIndex(start=0, stop=3, step=1)
27 
28 pn.major_xs(1)  # 输出的是DataFram
29 pn.to_frame()  # 转换为DataFrom格式