Python中dataframe\ array\ list相互转化

 import pandas as pd

 import numpy as np

 #创建列表

 a1=[1,2,3]

 #arange函数：指定初始值、终值、步长来创建数组

 a2=np.arange(0,1,0.1)

 #创建数据框

 a3=pd.DataFrame({'a':[1,2,3],'b':[4,5,6],'c':[7,8,9]})

#1、list 转化成array矩阵

b1 = np.array(a1).T

Out[30]: array([1, 2, 3])

　　

#2、array转化成dataframe

b2 = pd.DataFrame(a2)

Out[32]:

     0

0  0.0

1  0.1

2  0.2

3  0.3

4  0.4

5  0.5

6  0.6

7  0.7

8  0.8

9  0.9

b2.info()

<class 'pandas.core.frame.DataFrame'>

RangeIndex: 10 entries, 0 to 9

Data columns (total 1 columns):

0    10 non-null float64

dtypes: float64(1)

memory usage: 160.0 bytes

　　

#3、把Pandas中的dataframe转成numpy中的array

b3=a3.values

Out[35]:

array([[1, 4, 7],

       [2, 5, 8],

       [3, 6, 9]], dtype=int64)