數據類型轉換篇

01

#coding:utf-8

import numpy as np

import pandas as pd

#創(chuàng)建list

data=[[2016,'hello',90],

  [2017,'world',70],

  [2018,'nice',80]]

#把list轉為series

ser = pd.Series(data,

                       index=['one','two','three'])

#把seires轉為matrix

mat = ser.as_matirx()

#list轉為Dataframe

df=np.Dataframe(data,

index=['one','two','three'],

columns=['year','flag','status'])

#dataframe轉為ndarray

array1 = df.as_matrix()

array2 = df.values

array3 = np.array(df)

array_1 = df.as_matrix(['status'])

02

#coding:utf-8

import numpy as np

import pandas as pd

#創(chuàng)建dict

data = {'year':[2016,2017,2018],

         'flag':['hello','world','nice'],

         'status':[90,70,80]}

#把dict轉為seires;

#不指定index時，data的key則會為Series的index

ser = pd.Series(data)

#把dict轉為Dataframe;

#不指定columns,data的key充當DataFrame的columns

df = pd.DataFrame(data)

03

#coding:utf-8

import numpy as np

import pandas as pd

#創(chuàng)建數組array

data=np.array([[2016,'hello',90],

[2017,'world',70],

[2018,'nice',80]])

#數組轉為DataFrame

df = pd.DataFrame(data,

                            index=['one','two','three'],

    columns=['year','flag','status'])

#DataFrame轉為矩陣（數組）

array1 = df.as_matrix()

array2 = df.values

array3 = np.array(df)

#將某一列轉為數組

array_1 = df.as_matrix(['status'])

作者：黑馬程序員javaEE培訓學院
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