Python學(xué)習(xí)之旅 讀書筆記系列

Day 15

《Python編程從入門到實(shí)踐》

復(fù)盤：第一部分基礎(chǔ)知識(shí)（第1章~11章）

練習(xí)題

第6章 字典

認(rèn)識(shí)字典及其處理方式

1.my_friends.py

初識(shí)字典及字典的鍵-值獲取

my_friend = {
    "first_name":"zou","last_name":"jie",
    "age":"32","city":"shenzhen",
    }
#注意冒號(hào)在鍵跟值中間,分行時(shí)左右花括號(hào)的位置，以及養(yǎng)成習(xí)慣最后一組預(yù)留”,“
print(my_friend["first_name"])
print(my_friend["city"].upper())
print(my_friend["last_name"].title())

favorite_number = {}
favorite_number["Jie_zou"] = 8
favorite_number["Wedny_tu"] = 9
favorite_number["Jason_zou"] = 5
favorite_number["Smile_zou"] = 6
favorite_number["Eric_liu"] = 3
print("Jie_zou's favorite number is " + str(favorite_number["Jie_zou"]) + ".")
print("Smile_zou's favorite number is " +
    str(favorite_number["Smile_zou"]) + ".")
#打印時(shí)斷行，在合適地方分拆

word_list = {}
word_list["print"] = "打印"
word_list["while"] = "循環(huán)"
word_list["if"] = "條件判斷"
word_list["range"] = "列表"
word_list["tuple"] = "元組"
print("print:" + word_list["print"])
print("\nwhile:" + word_list["while"])
print("range:" + word_list["range"])
#特別留意換行符在冒號(hào)內(nèi),且放在換行行的句前

輸出結(jié)果如下：

2.word_list.py

字典的遍歷：鍵-值對(duì)，鍵，值

word_list = {}
word_list["print"] = "打印"
word_list["while"] = "循環(huán)"
word_list["if"] = "條件判斷"
word_list["range"] = "列表"
word_list["tuple"] = "元組"
for word, mean in word_list.items():
    """遍歷字典中的鍵-值對(duì)"""
    print("\nWord:" + word)
    print("Mean:" + mean)
word_list["sort"] = "排序"
word_list["len"] = "字段長(zhǎng)度"
word_list["strip"] = "去除空格"
word_list["string"] = "字符串"
word_list["python_zen"] = "Python之禪"
for word, mean in word_list.items():
    """添加5組數(shù)據(jù)之后，再遍歷字典中的鍵-值對(duì)"""
    print("\nWord:" + word)
    print("Mean:" + mean)

river_list = {}
river_list["nile"] = "egypt"
river_list["changjiang"] = "china"
river_list["amazon"] = "america"
for river,country in river_list.items():
    """一起提取鍵-值對(duì)中的鍵和值, items后面不要忘記括號(hào)"""
    print("\nThe " + river.title() + "runs through " + country.title() + ".")
for river in river_list.keys():
    """key,value后面記得加s"""
    print("\n" + river)
for country in river_list.values():
    print("\n" + country.title())

輸出結(jié)果如下：

3.favorite_languages.py

字典與列表的綜合運(yùn)用，范圍和條件判斷

favorite_languages = {
    'jen':'python',
    'sarah':'c',
    'edward':'ruby',
    'phil':'python',
    }
survey_list = [
    'jen','sarah',
    'jason','edward',
    'smile','phil'
    ]
for name in survey_list:
    """嵌套時(shí)，注意字典范圍和判斷的先后，keys后面小括號(hào)不要忘記"""
    if name in favorite_languages.keys():
        print('Thanks for your support!')
    else:
        print('Please help to intend the survey!')

輸出結(jié)果如下：

其他

• 感受及注意事項(xiàng)
  • 如果多行定義字典時(shí)，先輸左花括號(hào)，下一行記得“縮進(jìn)4個(gè)空格并以逗號(hào)結(jié)尾”，最后一行結(jié)尾時(shí)仍然加上“，”為添加鍵-值做準(zhǔn)備
  • 打印時(shí)分行，記得在合適的地方拆分，末尾加上拼接符（+）
  • 遍歷時(shí)：.item()為鍵-值對(duì)，.keys()為鍵，.values()為值，要剔除重復(fù)值時(shí)加上集合set(字典.values())