Python语言快速上手
最近在学习Python，后面搞机器人项目需要用到，所以要快速上手，我使用的是PyCharm这个IDE，看起来就舒服，学习起来就有劲啦，作为一名有工作经验的老司机，我学习编程语言的方法不会像大学生那样从头到尾学一遍，我会选择，够用，能用，实用即可，拒绝晦涩的语法，在不影响效率的情况下，我会采取容易看懂，后期项目可维护性等的方式来学习和编程，至于如何灵活运用Python语言，我认为是需要在项目中，才能不断精进的，毕竟，作为一门编程语言，它仅仅只是工具而已。
下面开始吧，首先：
如果要在python中写中文，则要在xx.py的最前面声明
#coding:utf-8
一、基础语法：变量，字符串，函数，逻辑判断，循环
varline = 2 ; print(varline); #打印字符串 print("hello Python"); print("你好，Python"); #整型和字符串的转化 num1 = 100 ; num2 = "100"; num3 = num1 + int(num2); print(num3); #字符串操作 str1 = "hello world" ; str2 = str1 * 3 ; string_count = len(str1); print(string_count); print(str2); #字符串索引等价 print(str1[0]); print(str1[-11]) #===>h print(str1[1]); print(str1[-10]) #===>e print(str1[2]); print(str1[-9]) #===>l #可以将字符串进行分割 print(str1[0:5]);print(str1[6:11]); #===> hello world print(str1[-4:]); #函数的定义和使用 def Print(): print("hello world"); return "sss" ; sss = Print(); print(sss); def add(arg1 , arg2): return arg1 + arg2 ; print(add(1,2)); def getTempatuare(temp): return temp *9/5 + 32 ; print(str(getTempatuare(35)) + "'F"); #克转千克算法 def print_kg(g): return float(g / 1000) ; print(str(print_kg(1)) + "kg"); #求直角三角形斜边的长度 def Line_print(arg1,arg2): return ((arg1*arg1 + arg2 * arg2))**0.5 print("The right triangle third side's length is " + str(Line_print(3,4))); #str_rp = str1.replace(str1[:3],'*'*9); #print(str_rp) str11 = "{} a word she can get what she {} for." str12 = "{preposition} a word she can get what she {verb} for" str13 = "{0} a word she can get what she {1} for." str111 = str11.format('With','came'); str121 = str12.format(preposition = 'With',verb = 'came') str131 = str13.format('With','came') print(str111) print(str121) print(str131) #单独创建 file1 = open('F:\\'+'hello.txt','w') file1.write("Hello world"); file1.close() #使用函数创建 def text_create(name, msg): desktop_path = 'F:\\' full_path = desktop_path + name + '.txt' file = open(full_path,'w') file.write(msg) file.close() print('Done') text_create('Yang','hello world') # ???? #变量的比较 teststr1 = "Hello" teststr2 = "World" teststr3 = "Hello" print(teststr1 in teststr2) print(teststr1 is teststr3) print(bool(teststr1)) print(bool('')) print(not teststr1) print(teststr1 < teststr3 and teststr2 > teststr1) print(teststr1 > teststr2 or teststr3 < teststr1) #python逻辑判断学习 a = 1 b = 3 if a < b : a = 3 b = 2 else: a = 2 b = 3 print(a,b); if a < b: a = 3 b = 2 elif a > b: a = 2 b = 3 else: a = 100 b = 200 print(a,b) for i in 1,2,3,4,5,6: print(i) for string_str in "hello","world","world": print(string_str) for str1111 in "Hello": print(str1111)
二、Python数据结构:列表，元组，字典，集合
#python列表===> #特点：可以装python的所有类型，包括元组，列表，字典等 city = ['广东','云南','广西','江西','HongKong','Shenzhen',123456] for i in 0,1,2,3,4,5,6: print(city[i]) city.insert(1,'北京') #列表的插入 for i in 0,1,2,3,4,5,6: print(city[i]) city.remove('HongKong') #列表的删除 for i in 0,1,2,3,4,5,6: print(city[i]) del city[0] #使用del方法删除列表中的元素 for i in 0,1,2,3,4,5: print(city[i]) #python元组 ===> #特点：不可修改，可被查看以及索引 num = ('1','2','3','4','5') for i in 0,1,2,3,4: print(num[i]) #python字典 ===> #特点：键值成对存在，键不可重复，值可重复，键不可改，值可以变，可以为任何对象 Dog = {'name':'sundy','age':18} Dog.update({'tel':119}) #往字典中添加键值对 print(Dog) del Dog['name'] #往字典中删除键值对 print(Dog) 集合 num_set = {1,2,3,4,1,5} num_set.add(6) #往集合里添加元素 print(num_set) num_set.discard(3) #从集合里删除元素 print(num_set)
三、Python语言面对对象:类的定义、使用以及类的继承
#coding:utf-8 #定义一个类 class Anmial: var = 100 Dog = ['runing','eat','sleep'] #Dog是这个类的属性 def function(self): #类里的方法 if Anmial.var == 10: print(Anmial.var) else: print(self+str(Anmial.Dog)) return Anmial.var #实例化类 Dog1 = Anmial() print(Anmial.Dog) #遍历类中的成员 for i in Anmial.Dog: print(i) #创建实例属性===>类似创建一个与Dog一样的属性 Anmial.log = '会飞','Hello','Monkey' print(Anmial.log) Anmial.function("属性:") class CocaCola(): formula = ['caffeine','suger','water','soda'] def __init__(self,local_name): #===>self相当于可以用来访问类中的成员或者创建属性 self.logo_local = '橙汁' if local_name == '可乐': print(local_name) elif local_name == '橙汁': print(local_name) else: print('西瓜汁') def drink(self): #===>调用该方法的时候等效于 coke = CocaCola.drink(coke) print('Energy!') coke = CocaCola('可乐') coke1 = CocaCola('橙汁') coke2 = CocaCola('梨汁') #类的继承===>xuebi相当于CocaCoal的子类,CocaCoal相当于父类 class xuebi(CocaCola): formula = ['白色','黄色','绿色'] xuebi = xuebi(CocaCola) #将CocaCola放在括号中，表面xuebi集成于CocalCola print(xuebi.formula) xuebi.drink() #这样子类就可以调用父类的方法，继续延用了
