数据类型转换篇

01

#coding:utf-8

import numpy as np

import pandas as pd

#创建list

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

  [2017,'world',70],

  [2018,'nice',80]]

#把list转为series

ser = pd.Series(data,

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

#把seires转为matrix

mat = ser.as_matirx()

#list转为Dataframe

df=np.Dataframe(data,

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

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

#dataframe转为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

#创建dict

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

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

         'status':[90,70,80]}

#把dict转为seires;

#不指定index时，data的key则会为Series的index

ser = pd.Series(data)

#把dict转为Dataframe;

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

df = pd.DataFrame(data)

03

#coding:utf-8

import numpy as np

import pandas as pd

#创建数组array

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

[2017,'world',70],

[2018,'nice',80]])

#数组转为DataFrame

df = pd.DataFrame(data,

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

    columns=['year','flag','status'])

#DataFrame转为矩阵（数组）

array1 = df.as_matrix()

array2 = df.values

array3 = np.array(df)

#将某一列转为数组

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

作者：黑马程序员javaEE培训学院
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