Python列表截取:
使用索引下标查看列表元素:
lst = ['a','b','c','d','e','f','g','h'] print(lst[0]) # a print(lst[3]) # d print(lst[7]) # h # 当索引下标为负数时,-1表示最右端元素,从右向左依次递减 print(lst[-1]) # h print(lst[-4]) # e
列表名[start:end:step]:
使用切片截取列表元素(不包含end)
# 使用切片进行截取列表元素 # lst = [i for i in range(1,11)] lst = [1,2,3,4,5,6,7,8,9,10] print(lst[::]) # [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] print(lst[2:8]) # [3, 4, 5, 6, 7, 8] print(lst[2:8:3]) # [3, 6] , 不包含end print(lst[2::-1]) # [3, 2, 1] print(lst[8:1:-1]) # [9, 8, 7, 6, 5, 4, 3] print(lst[8:1:-2]) # [9, 7, 5, 3] print(lst[-1:-5:-1]) # [10, 9, 8, 7]
+= 对列表进行拼接操作:
# += 对列表进行拼接操作: lst = [1,2,3] lst += [4,5,6] print(lst) # [1, 2, 3, 4, 5, 6]
2020-02-09