在Python中过滤字典

Question

这是我的代码：

import csv
import os

filename = "StudentsPerformance.csv"
file = open(filename, "r", encoding="utf-8")
contents = csv.reader(file)


students = []
column_names = next(contents)
for row in contents:
    student = {
        "gender": row[0],
        "race/ethnicity": row[1],
        "parental level of education": row[2],
        "lunch": row[3],
        "test preparation course": row[4],
        "math score": row[5],
        "reading score": row[6],
        "writing score": row[7],
    }
    students.append(student)




def math_scores(student):
    return int(student["math score"])


def average_math_scores(student):
    scores = list(map(math_scores, students))
    total_scores = sum(scores)
    number_of_scores = len(scores)
    average_scores = total_scores / number_of_scores
    print(average_scores)
    return average_scores



if __name__ == '__main__':
    average_math_scores(students)

我怎样才能制作一个过滤器，以便男性和女性得到自己的字典。这样我就有一个字典，其中包含所有数据，称为女性，男性的数据也相同。我已经定义了称为“女性”和“男性”的两个字典。

Answer 1

使用python3

我假设这是您的数据，代码也应该适用于更多字段：

students=[{"gender":'m',"math_score":'A'},
          {"gender":'f',"math_score":'B'},
          {"gender":'m',"math_score":'D'},
          {"gender":'f',"math_score":'C'}]

您可以使用内置filter函数：

males=list(filter(lambda x:x["gender"]=='m',students))
females=list(filter(lambda x:x["gender"]=='f',students))

请参阅过滤器功能的文档。