Python |熊猫分类数据框创建
原文:https://www.geesforgeks.org/python-pandas-classic-data frame-creation/
熊猫。DataFrame(dt type = " category "):为了创建分类数据帧，data frame()方法将 dt type 属性设置为 category。 通过在数据框构造函数中指定 dtype =“category ”,数据框中的所有列都可以在构造期间或之后转换为分类。
代码:
# 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 : \n", df1)
print("\n\ndf1 type :\n", df1.dtypes)
输出:
# Converting dataframe to category
df2 = pd.DataFrame({'A': list('1245'), 'B': list('3456')}, dtype ="category")
print ("df2 : \n", df2)
print("\n\ndf2 type :\n", df2.dtypes)
print ("\n\ndf2 column 0 :\n", df2['A'])
print ("\n\ndf2 column 1 :\n", df2['B'])
输出:
# Conversion can be done using astype()
df3 = pd.DataFrame({'A': list('efgh'), 'B': list('aebc')})
print ("\n\ndf3 : \n", df3)
print("\ndf3 type :\n", df3.dtypes)
df4 = df3.astype('category')
print ("\n\ndf4 type:\n", df4.dtypes)
输出:
