Python Pandas - 基于基础分类创建索引
要基于底层Categorical创建索引,请使用方法。pandas.CategoricalIndex()
首先,导入所需的库-
import pandas as pd
CategoricalIndex是基于基础Categorical的指数。CategoricalIndex只能采用有限且通常是固定数量的可能值。使用“categories”参数设置分类的类别。使用“ordered”参数按顺序处理分类-
catIndex = pd.CategoricalIndex( ["p", "q", "r", "s","p", "q", "r", "s"], ordered=True, categories=["p", "q", "r", "s"] )
显示分类索引-
print("Categorical Index...\n",catIndex)
获取类别-
print("\nDisplayingCategories from CategoricalIndex...\n",catIndex.categories)
示例
以下是代码-
import pandas as pd #CategoricalIndex是基于基础CategoricalIndex的指数 # Set the categories for the categorical using the "categories" parameter # Treat the categorical as ordered using the "ordered" parameter catIndex = pd.CategoricalIndex( ["p", "q", "r", "s","p", "q", "r", "s"], ordered=True, categories=["p", "q", "r", "s"] ) #显示分类索引 print("Categorical Index...\n",catIndex) #获取类别 print("\nDisplayingCategories from CategoricalIndex...\n",catIndex.categories) #获取最小值 print("\nMinimum value from CategoricalIndex...\n",catIndex.min()) #获取最大值 print("\nMaximum value from CategoricalIndex...\n",catIndex.max())输出结果
这将产生以下输出-
Categorical Index... CategoricalIndex(['p', 'q', 'r', 's', 'p', 'q', 'r', 's'], categories=['p', 'q', 'r', 's'], ordered=True, dtype='category') DisplayingCategories from CategoricalIndex... Index(['p', 'q', 'r', 's'], dtype='object') Minimum value from CategoricalIndex... p Maximum value from CategoricalIndex... S