要从 DataFrame 中的列中获取唯一值,请使用unique(). 要计算 DataFrame 中某一列的唯一值,请使用nunique().
首先,导入所需的库 -
import pandas as pd;
创建一个包含 3 列的 DataFrame。我们也有重复的值 -
dataFrame = pd.DataFrame( { "Car": ['BMW', 'Audi', 'BMW', 'Lexus', 'Tesla', 'Lexus', 'Mustang'],"Place": ['Delhi','Bangalore','Hyderabad','Chandigarh','Pune', 'Mumbai', 'Jaipur'],"Units": [100, 150, 50, 110, 90, 120, 80] } )
使用计数获取唯一值 -
print"\nUnique values from a column ...\n",dataFrame['Car'].unique() print"\nCount unique values from a column ...\n",dataFrame['Car'].nunique()
以下是代码 -
import pandas as pd; # create a DataFrame dataFrame = pd.DataFrame( { "Car": ['BMW', 'Audi', 'BMW', 'Lexus', 'Tesla', 'Lexus', 'Mustang'],"Place": ['Delhi','Bangalore','Hyderabad','Chandigarh','Pune', 'Mumbai', 'Jaipur'],"Units": [100, 150, 50, 110, 90, 120, 80] } ) print"DataFrame ...\n",dataFrame # get unique values from a column print"\nUnique values from a column ...\n",dataFrame['Car'].unique() print"\nCount unique values from a column ...\n",dataFrame['Car'].nunique()输出结果
这将产生以下输出 -
DataFrame ... Car Place Units 0 BMW Delhi 100 1 Audi Bangalore 150 2 BMW Hyderabad 50 3 Lexus Chandigarh 110 4 Tesla Pune 90 5 Lexus Mumbai 120 6 Mustang Jaipur 80 Unique values from a column ... ['BMW' 'Audi' 'Lexus' 'Tesla' 'Mustang'] Count unique values from a column ... 5