List

# 使用 for loop 定義 number 為 my_list 中的各項數據
# 使 my_list 不被變更，可重複使用

my_list = [1,9,3,8,5,7]
  for number in my_list:
    print(2 * number)

2
18
6
16
10
14

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# 也可另外創一個 empty list
# 視情況去增加 .append() 或 排列 .sort()

start_list = [5, 3, 1, 2, 4]
square_list = []
  for number in start_list:
    square_list.append(number ** 2)
    square_list.sort()

print (square_list)

[1, 4, 9, 16, 25]

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Index的種類

# (start, stop, step)
# 第3個數字=step，跳n個來數

squares=[0,1,4,9,16,25,36,49,64,81]
print(square[::2])
print(square[2:8:3]) # index 2 ~ index 8 之間，往後數第3個

[0,4,16,36,64]
[4,25]

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# Index為負數 : 從後面數回來

squares=[0,1,4,9,16,25,36,49,64,81]
print(square[1:-1])

[1,4,9,16,25,36,49,64]

squares=[0,1,4,9,16,25,36,49,64,81]
print(square[7:5:-1])

[49, 36]

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#　指定刪除list的其中一個

backpack = ['xylophone', 'dagger', 'tent', 'bread loaf']
backpack.remove('dagger')
print(backpack)

[‘xylophone’, ‘tent’, ‘bread loaf’]

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