Python編程入門到實踐 - 筆記（ 4 章）

時間 2020-01-05

標籤 python 編程入門實踐筆記欄目 Python 简体版

原文原文鏈接

昨天下午又看了一遍第4章，今天早上本身來個總結吧。python

複習內容以下：git

經過 for 循環遍歷表中內容以及在循環中打印和循環外打印app

rang() 建立列表和設置步長ide

數字列表的簡單統計spa

1）mix 最小索引

2）max 最大three

3）sum 和ci

C語言風格的運算加 for 循環it

列表中元素的切片，賦值列表io

遍歷元組以及元組的從新賦值

經過 for 循環遍歷列表中的內容

---------------------------------------------------

magicians = ['alice', 'david', 'carolina']
for magician in magicians:
print(magician)

---------------------------------------------------

alice
david
carolina

在 for 循環中執行更多的操做，告訴每一位魔術師期待他的下一次表演

-----------------------------------------------------------------------------

magicians = ['alice', 'david', 'carolina']
for magician in magicians:
print(magician.title() + ", that was a great trick!")
print("I can't wait to see your next trick, " + magician.title() + ".\n")

------------------------------------------------------------------------------

Alice, that was a great trick!
I can't wait to see your next trick, Alice.

David, that was a great trick!
I can't wait to see your next trick, David.

Carolina, that was a great trick!
I can't wait to see your next trick, Carolina.

在 for 循環結束後執行一些操做

------------------------------------------------------------------------------

magicians = ['alice', 'david', 'carolina']
for magician in magicians:
print(magician.title() + ", that was a great trick!")
print("I can't wait to see your next trick, " + magician.title() + ".\n")
print("Thank you, everyone. That was a great magic show!")

-------------------------------------------------------------------------------

Alice, that was a great trick!
I can't wait to see your next trick, Alice.

David, that was a great trick!
I can't wait to see your next trick, David.

Carolina, that was a great trick!
I can't wait to see your next trick, Carolina.

Thank you, everyone. That was a great magic show!

range()建立數值列表

這裏的 range() 只打印數字 1~4，range() 會在達到指定的第二個值時中止打印

----------------------------------------

for value in range(1,5):
print(value)

----------------------------------------

1
2
3
4

使用 range() 建立數字列表

------------------------------------

numbers = list(range(1,6))
print(numbers)

------------------------------------

[1, 2, 3, 4, 5]

range() 還能夠在第三位指定步長

第三位指定 2，表示數字不斷 +2 打印

--------------------------------------------

numbers = list(range(1,11,2))
print(numbers)

--------------------------------------------

[1, 3, 5, 7, 9]

將前 10 個整數平方加入到一個列表中

--------------------------------------------

squares = []
for value in range(1,11):
square = value ** 2
squares.append(square)

print(squares)

---------------------------------------------

[1, 4, 9, 16, 25, 36, 49, 64, 81, 100]

對數字列表執行簡單的統計

min 最小

max 最大

sum 和

--------------------------------------------

digits = [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 0]
print(min(digits))
print(max(digits))
print(sum(digits))

--------------------------------------------

0
9
45

C 語言風格的列表解析

------------------------------------------------------------

squares = [ value**2 for value in range(1,11) ]
print(squares)

------------------------------------------------------------

[1, 4, 9, 16, 25, 36, 49, 64, 81, 100]

使用列表的一部分（切片）

取出列表的前三個元素

-----------------------------------------------------------------------

players = ['charles', 'martina', 'michael', 'florence', 'eli']
print(players[0:3])

------------------------------------------------------------------------

['charles', 'martina', 'michael']

取出列表的第 2~4 個元素

-----------------------------------------------------------------------

players = ['charles', 'martina', 'michael', 'florence', 'eli']
print(players[1:4])

-----------------------------------------------------------------------

['martina', 'michael', 'florence']

若是沒有指定索引，python 會自動從頭開始切

-----------------------------------------------------------------------

players = ['charles', 'martina', 'michael', 'florence', 'eli']
print(players[:4])

-----------------------------------------------------------------------

['charles', 'martina', 'michael', 'florence']

中括號裏面的第二位不指定，表明終止於列表末尾

打印從第三個到列表末尾的全部元素

-----------------------------------------------------------------------

players = ['charles', 'martina', 'michael', 'florence', 'eli']
print(players[2:])

-----------------------------------------------------------------------

['michael', 'florence', 'eli']

打印列表中最後三個元素

-----------------------------------------------------------------------

players = ['charles', 'martina', 'michael', 'florence', 'eli']
print(players[-3:])

-----------------------------------------------------------------------

['michael', 'florence', 'eli']

遍歷切片

只遍歷列表的部分元素，打印前三個元素

-----------------------------------------------------------------------

players = ['charles', 'martina', 'michael', 'florence', 'eli']
print("Here are the first three players on my team:")
for player in players[:3]:
print(player.title())

-----------------------------------------------------------------------

Here are the first three players on my team:
Charles
Martina
Michael

複製列表

經過 [ : ] 複製一個新列表

--------------------------------------------------------

my_foods = ['pizza', 'falafel', 'carrot cake']
friend_foods = my_foods[:]

print("My favorite foods are:")
print(my_foods)

print("\nMy friend's favorite foods are:")
print(friend_foods)

--------------------------------------------------------

My favorite foods are:
['pizza', 'falafel', 'carrot cake']

My friend's favorite foods are:
['pizza', 'falafel', 'carrot cake']

給兩個列表分別添加元素，證實咱們確實打印的是兩個表