Python从列表中删除值的多种实用方法

fruits = ["apple", "banana", "orange", "banana"]
fruits.remove("banana")  # 删除第一个出现的 "banana"
print(fruits)  # 输出: ["apple", "orange", "banana"]

numbers = [10, 20, 30, 40]
# 删除索引为1的元素(20)
removed_num = numbers.pop(1)
print(f"删除的元素：{removed_num}")  # 输出: 删除的元素：20
print(numbers)  # 输出: [10, 30, 40]
 
# 删除最后一个元素(40)
last_num = numbers.pop()
print(f"最后一个元素：{last_num}")  # 输出: 最后一个元素：40

langs = ["Python", "Java", "C++", "Go", "Rust"]
 
# 删除单个元素(索引为2的"C++")
del langs[2]
print(langs)  # 输出: ["Python", "Java", "Go", "Rust"]
 
# 删除切片(索引1到3的元素，不包含3)
del langs[1:3]
print(langs)  # 输出: ["Python", "Rust"]

scores = [85, 90, 78, 92, 85]
# 过滤掉所有85分
new_scores = [x for x in scores if x != 85]
print(new_scores)  # 输出: [90, 78, 92]
print(scores)       # 原列表不变: [85, 90, 78, 92, 85]

temp_list = [1, 2, 3, 4]
temp_list.clear()
print(temp_list)  # 输出: []

# 错误示例：跳过部分元素
words = ["a", "b", "a", "a", "c"]
for i in range(len(words)):
    print(f"索引 {i}: {words[i]}")
 
for word in words:
    if word == "a":
        words.remove(word)
print(words)  # 输出: ['b', 'a', 'c']
 
for i in range(len(words)):
    print(f"索引 {i}: {words[i]}")

words = ["a", "b", "a", "a", "c"]
for i in range(len(words)):
    print(f"索引 {i}: {words[i]}")
# 从后往前遍历，避免索引混乱
for i in range(len(words)-1, -1, -1):
    if words[i] == "a":
        words.pop(i)
print(words)  # 输出: ["b", "c"]
for i in range(len(words)):
    print(f"索引 {i}: {words[i]}")]

words = ["a", "b", "a", "c"]
# 遍历原列表的副本，操作原列表
for word in list(words):
    if word == "a":
        words.remove(word)
print(words)  # 输出: ["b", "c"]

data = [10, 20, 30, 40, 50, 60]
indices = [1, 3, 5]  # 待删除的索引
 
# 倒序排序索引，避免删除后索引错位
for idx in sorted(indices, reverse=True):
    data.pop(idx)
 
print(data)  # 输出: [10, 30, 50]

nums = [1, 2, 3, 4, 5]
# 过滤出所有奇数
odds = list(filter(lambda x: x % 2 == 1, nums))
print(odds)  # 输出: [1, 3, 5]

from itertools import filterfalse
nums = [1, 2, 3, 4, 5]
 
# 保留偶数(删除奇数)
evens = list(filterfalse(lambda x: x % 2 == 1, nums))
print(evens)  # 输出: [2, 4]