Python中多返回值的应用场景

import sqlite3

def query_db(query):
    conn = sqlite3.connect('example.db')
    cursor = conn.cursor()
    cursor.execute(query)
    rows = cursor.fetchall()
    conn.close()
    return [(row[0], row[1], row[2]) for row in rows]

# 使用函数
for id, name, age in query_db("SELECT id, name, age FROM users"):
    print(f"ID: {id}, Name: {name}, Age: {age}")

import os

def get_file_info(filepath):
    size = os.path.getsize(filepath)
    modification_time = os.path.getmtime(filepath)
    with open(filepath, 'r') as file:
        content = file.read()
    return size, modification_time, content

# 使用函数
size, mod_time, content = get_file_info('example.txt')
print(f"Size: {size} bytes, Modified: {mod_time}, Content: {content[:100]}...")  # 显示部分内容

import numpy as np

def process_array(arr):
    min_val = np.min(arr)
    max_val = np.max(arr)
    mean_val = np.mean(arr)
    return min_val, max_val, mean_val

# 创建一个二维数组
array = np.array([[1, 2, 3], [4, 5, 6]])

# 使用函数
min_val, max_val, mean_val = process_array(array)
print(f"Min: {min_val}, Max: {max_val}, Mean: {mean_val}")

def higher_order_func(data, func):
    return map(func, data)

# 定义一个返回多个值的函数
def get_details(x):
    return x**2, x**3

# 使用高阶函数和多返回值
results = higher_order_func(range(1, 4), get_details)
for square, cube in results:
    print(f"Square: {square}, Cube: {cube}")

def divide(x, y):
    try:
        return x / y, "Success"
    except ZeroDivisionError:
        return None, "Division by zero error"

# 使用函数
result, status = divide(10, 0)
if result is not None:
    print(f"Result: {result}")
else:
    print(status)