如何使列中的相似值相等

Question

我有一个这样的数据框：

Student_ID   Subject       Class_Feedback_question    Class_Feedback_Answer
100101       Physics       How was physics class?     Excellent: 5 
100101       Physics       how was physics class:     very good:4  
100101       Physics       How was the Presentation:  Good: 3  
100101       Chemistry     How Much would you rate?   Excellent: 5 
100102       Math          how much would you rate:   Excellent: 4
100102       Physics       how was presentation:      Good: 3

我想让Class_Feedback_question 列中相似的行值看起来相等，（例如：在问题or 的末尾将: 设为? 保持一个问题不变，并用它替换其他类似的问题，例如：how was presentation: 替换为 How was the Presentation: ) 像这样：

Student_ID   Subject       Class_Feedback_question     Class_Feedback_Answer
100101       Physics       How was physics class?      Excellent: 5 
100101       Physics       How was physics class?      very good:4  
100101       Physics       How was the presentation:   Good: 3  
100101       Chemistry     How Much would you rate?    Excellent: 5 
100102       Math          How much would you rate?    Excellent: 4
100102       Physics       How was the presentation:   Good: 3

如何在python Pandas 中做到这一点？ 另外，如何根据Class_Feedback_Answer 创建数据透视表？

Answer 1

将 ':' 替换为 '?'你可以使用apply方法

df['Class_Feedback_question'] = df['Class_Feedback_question'].apply(x: x.replace(':', '?'))

要重新表述问题，您必须逐案处理，我建议使用map 方法

rephrasing = {'how was presentation': 'How was the presentation'}
df['Class_Feedback_question'] = df['Class_Feedback_question'].map(rephrasing)

对于数据透视表，请查看 pandas 文档，因为您没有提供足够的信息。真的很清楚：https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.DataFrame.pivot.html?highlight=pivot#pandas.DataFrame.pivot