heyong.fu
53 lines
1.5 KiB
Python
53 lines
1.5 KiB
Python
# Lambda函数，也称为匿名函数，是Python中一种轻量级、简洁的函数定义方式。与常规的def函数不同，Lambda函数没有名字，可以在需要短小函数的地方直接使用。
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# 基本特点：
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# 匿名性：Lambda函数没有函数名
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# 简洁性：通常用于简单的单行表达式
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# 临时性：适合临时使用的功能
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# 函数式编程：与高阶函数配合使用
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add = lambda x, y: x + y
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print(add(1, 2))
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square = lambda x: x**2
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print(square(2))
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# 应用
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# 排序
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words = ["apple", "banana", "cherry", "date", "elderberry"]
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words.sort(key=lambda x: len(x))
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print(words)
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# 按字符创长度降序拍
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words = ["apple", "banana", "cherry", "date", "elderberry"]
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words.sort(key=lambda x: len(x), reverse=True)
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print(words)
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students = [
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{"name": "Alice", "age": 20, "grade": 85},
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{"name": "Bob", "age": 19, "grade": 92},
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{"name": "Charlie", "age": 21, "grade": 78},
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]
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# 按年龄排序
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students_by_age = sorted(students, key=lambda x: x["age"])
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print(students_by_age)
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# 按成绩排序
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students_by_grade = sorted(students, key=lambda x: x["grade"], reverse=True)
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print(students_by_grade)
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# 在列表中使用lambda
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numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
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squared_numbers = [(lambda x: x**2)(item) for item in numbers]
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print(squared_numbers)
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# 进行条件过滤
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large_numbers = [num for num in numbers if (lambda x: x > 5)(num)]
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print(large_numbers)
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# 转大写
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texts = ["hello", "world", "python", "programming"]
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upper_texts = [(lambda x: x.upper())(w) for w in texts]
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print(upper_texts)
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