Python入門篇（三）之列表

標籤：Python

1、列表定義

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"] #列表格儲存體，類似數組

2、列表的操作（1）切片

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"] #列表格儲存體，類似數組print(names[1],names[3]) #取值，1、3代表下標，從左至右的位置執行結果：Guyun Xuliangchenprint(names[1:3]) #切片,顧頭不顧尾取[1]、[2]的值print(names[0:3]) #切片print(names[:3]) #等同於0:3，從下標0到3print(names[-1]) #切片,取倒數第一個值print(names[-2]) #取倒數第二個值print(names[-2:]) #取最後兩個值

（2）增加--append：

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]names.append("LeiHaidong") #追加到最後print(names)執行結果：[‘ZhangYang‘, ‘Guyun‘, ‘Xiangpeng‘, ‘Xuliangchen‘, ‘LeiHaidong‘]

（3）修改--insert：

names.insert(1,"Chenronghua")  #資料插入，插在哪個位置前面就寫這個元素的下標,如插在Guyun前面names.insert(3,"Xinzhiyu") #插在Guyun後面print(names)執行結果：[‘ZhangYang‘, ‘Chenronghua‘, ‘Guyun‘, ‘Xinzhiyu‘, ‘Xiangpeng‘, ‘Xuliangchen‘, ‘LeiHaidong‘]

（4）查詢--index：

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]print(names)print(names.index("Xiangpeng")) #查出Xiangpeng的位置print(names[names.index("Xiangpeng")]) #擷取下標內容執行結果：[‘ZhangYang‘, ‘Guyun‘, ‘Xiangpeng‘, ‘Xuliangchen‘]2Xiangpeng

（5）統計--count：

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]print("count-->",names.count("ZhangYang"))執行結果：count--> 1

（6）反轉--reverse:

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]names.reverse()print(names)執行結果：[‘ZhangYang‘, ‘Guyun‘, ‘Xiangpeng‘, ‘Xuliangchen‘]reverse--> [‘Xuliangchen‘, ‘Xiangpeng‘, ‘Guyun‘, ‘ZhangYang‘]

（7）擴充--extend：

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]names2 = [1,2,3,4]print(names)names.extend(names2)print("extend-->",names)執行結果：[‘ZhangYang‘, ‘Guyun‘, ‘Xiangpeng‘, ‘Xuliangchen‘]extend--> [‘ZhangYang‘, ‘Guyun‘, ‘Xiangpeng‘, ‘Xuliangchen‘, 1, 2, 3, 4]

（8）排序--sort：

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]names.sort()print(names)執行結果：[‘Guyun‘, ‘Xiangpeng‘, ‘Xuliangchen‘, ‘ZhangYang‘]

（9）清除--clear：

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]names.clear()print(names)執行結果：[]

（10）複製--copy：

names = ["ZhangYang","Guyun","Xiangpeng","Xuliangchen"]names2 = names.copy()print(names)print(names2)names[1] = "古雲"  #更改Guyun,可以看到names2中並沒有修改print("names-->",names)print("names2-->",names2)執行結果：[‘ZhangYang‘, ‘Guyun‘, ‘Xiangpeng‘, ‘Xuliangchen‘][‘ZhangYang‘, ‘Guyun‘, ‘Xiangpeng‘, ‘Xuliangchen‘]names--> [‘ZhangYang‘, ‘古雲‘, ‘Xiangpeng‘, ‘Xuliangchen‘]names2--> [‘ZhangYang‘, ‘Guyun‘, ‘Xiangpeng‘, ‘Xuliangchen‘]

（11）列表嵌套複製--copy.deepcopy：

names = ["ZhangYang","Guyun",["alex","jack"],"Xiangpeng","Xuliangchen"] names2 = names.copy()print(names)print(names2)names[1] = "古雲"names[2][0] = "ALEX" #更改列表中的alex為ALEX,可以看到names2中也相應更改print("names-->",names)print("names2-->",names2)執行結果：[‘ZhangYang‘, ‘Guyun‘, [‘alex‘, ‘jack‘], ‘Xiangpeng‘, ‘Xuliangchen‘][‘ZhangYang‘, ‘Guyun‘, [‘alex‘, ‘jack‘], ‘Xiangpeng‘, ‘Xuliangchen‘]names--> [‘ZhangYang‘, ‘古雲‘, [‘ALEX‘, ‘jack‘], ‘Xiangpeng‘, ‘Xuliangchen‘]names2--> [‘ZhangYang‘, ‘Guyun‘, [‘ALEX‘, ‘jack‘], ‘Xiangpeng‘, ‘Xuliangchen‘]★★★★注意：這裡的的copy只會拷貝第一層，列表中包含列表，其中列表是指向存放列表的記憶體位址，所以在更改列表中的元素時，拷貝的部分也會相應地更改。為了實現深入拷貝，可以匯入copy模組：import copynames2 = copy.deepcopy(names)print(names)print(names2)names[1] = "古雲"names[2][0] = "ALEX"print("names-->",names)print("names2-->",names2)執行結果：[‘ZhangYang‘, ‘Guyun‘, [‘alex‘, ‘jack‘], ‘Xiangpeng‘, ‘Xuliangchen‘][‘ZhangYang‘, ‘Guyun‘, [‘alex‘, ‘jack‘], ‘Xiangpeng‘, ‘Xuliangchen‘]names--> [‘ZhangYang‘, ‘古雲‘, [‘ALEX‘, ‘jack‘], ‘Xiangpeng‘, ‘Xuliangchen‘]names2--> [‘ZhangYang‘, ‘Guyun‘, [‘alex‘, ‘jack‘], ‘Xiangpeng‘, ‘Xuliangchen‘]可以看到拷貝是完全複製過來的，但是生產過程中一般不會使用，拷貝多一份資料，等於多佔據了一份記憶體空間。

（12）for迴圈列表：

names = ["ZhangYang","Guyun",["alex","jack"],"Xiangpeng","Xuliangchen"] for i in names:    print(i)執行結果：ZhangYangGuyun[‘alex‘, ‘jack‘]XiangpengXuliangchen

（13）步長切片：

names = ["ZhangYang","Guyun",["alex","jack"],"Xiangpeng","Xuliangchen"] print(names[0:-1:2]) #列印第一個到最後一個，步長為2執行結果：[‘ZhangYang‘, [‘alex‘, ‘jack‘]]

3、程式練習

程式：購物車程式

需求:

啟動程式後，讓使用者輸入工資，然後列印商品列表
允許使用者根據商品編號購買商品
使用者選擇商品後，檢測餘額是否夠，夠就直接扣款，不夠就提醒
可隨時退出，退出時，列印已購買商品和餘額

#!/usr/bin/python# _*_ coding:utf-8 _*_# Aothr: Kimgoods_list = [    [‘Iphone‘,5800],    [‘Mac pro‘,9800],    [‘Bike‘,800],    [‘Watch‘,10600],    [‘Coffee‘,31],    [‘Alex Python‘,120]]shopping_list = [] #此列表為空白當做購物車使用salary = input("Please input your salary:")if salary.isdigit():    salary = int(salary)    while True:        for index,item in enumerate(goods_list): #enumerate可以取出列表的下標和內容            print(index,item)        user_choice = input("請選擇你需要的商品編號：")        if user_choice.isdigit():            user_choice = int(user_choice)            if user_choice < len(goods_list) and user_choice >= 0: #len可以取出列表的長度                g_item = goods_list[user_choice]                if g_item[1] <= salary:                    shopping_list.append(g_item)                    salary -= g_item[1]                    print("已成功添加商品%s到購物車，當前餘額為\033[31;1m%s\033[0m" % (g_item, salary))                else:                    print("您的餘額為%s，無法購買此商品，請儲值！"%salary)            else:                print("您的選擇的商品編號%s有誤，請重新選擇:"%user_choice)        elif user_choice == ‘q‘:            print(‘------goods list------‘)            for p in shopping_list:                print(p)            print("您當前餘額為%s"%salary)            exit()        else:            print("您的輸入有誤，請輸入正確的商品編號！")

Python入門篇（三）之列表