Python |分类数据帧创建

# Python code explaining

# constructing categorical data frame

# importing libraries

import numpy as np

import pandas as pd

# Constructing dataframe

data = { 'col1' : [ 1 , 2 , 4 , 5 ], 'col2' : [ 3 , 4 , 5 , 6 ]}

df1 = pd.DataFrame(data = data)

print ( "df1 : " , df1)

print ( "df1 type :" , df1.dtypes)

# Converting dataframe to category

df2 = pd.DataFrame({ 'A' : list ( '1245' ), 'B' : list ( '3456' )}, dtype = "category" )

print ( "df2 : " , df2)

print ( "df2 type :" , df2.dtypes)

print ( "df2 column 0 :" , df2[ 'A' ])

print ( "df2 column 1 :" , df2[ 'B' ])

# Conversion can be done using astype()

df3 = pd.DataFrame({ 'A' : list ( 'efgh' ), 'B' : list ( 'aebc' )})

print ( "df3 : " , df3)

print ( "df3 type :" , df3.dtypes)

df4 = df3.astype( 'category' )

print ( "df4 type:" , df4.dtypes)