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