list基本操作

1、轮询

1.1 根据下标轮询

list = ["1","2","3","4"]
for i in range(len(list)):
 print("list[i]", list[i])

1.2 根据值轮询

list = ["1","2","3","4"]
for data in(list):
  print("data",data)

2、切片

2.1 代码

list = [1,2,3,4,5,6,7]
print("list[1:3] = ",list[1:3])
print("list[-1:] = ",list[-1:])
print("list[:-1] = ",list[:-1])
print("list[:3] = ",list[:3])
print("list[3:] = ",list[3:])

打印信息：
list[1:3] =  [2, 3]
list[-1:] =  [7]
list[:-1] =  [1, 2, 3, 4, 5, 6]
list[:3] =  [1, 2, 3]
list[3:] =  [4, 5, 6, 7]

3、tuple 和list 相互转化

tupleData = tuple(list)
print("tupleData = ",tupleData)
listData = list(tupleData)
print("listData = ", listData)

打印信息：
tupleData =  (1, 2, 3, 4, 5, 6, 7)
listData =  [1, 2, 3, 4, 5, 6, 7]

4、用某个固定值初始化列表

initial_value = 0
list_length = 5
sample_list = [ initial_value for i in range(10)]
sample_list = [initial_value]*list_length
# sample_list ==[0,0,0,0,0]