函数 def 等

'''def myfun(str): '我是解释的文字' print(str)#调用 定义和调用不能出错!myfun('这是第一次调用')myfun('这是第二次调用')参数没有类型 py不做类型检查不支持重载 !py不会区分参数名字和个数 多个同名函数时 后一个会覆盖前面一个 位置参数和关键字参数 函数调用 str num tuple不可变 集合可append值传递 引用传递 列表 字典def funcA(x,y,z): print(x,y,z)#调用函数 abvc() 封装 内置函数 自定义 javascript object notation# funcA('hello',12,True)# funcA('True,hello',121)# funcA(z=True,y=12,x='hello')def myfunc(a): a={3} return id( a)a = {2}print('调用前',id(a))print(myfunc(a))print('调用后',id(a))def funcB(mylist): '修改传入的列表' mylist.append(100) print('修改后的mylist:',mylist) returnmylist = [10,20,30]print("调用前的mylist:",mylist)#调用funcB(mylist)print("调用后的mylist:",mylist)必备参数 关键字参数 默认参数 不定长参数def funcA(str): #"打印" print(str) return#调用funcA函数funcA(str='python')def funcA(x,y,z): print(x,y,z)funcA(True,12,'hello')funcA(z=True,y=12,x="hello")def funcA(name,age=25): "打印" print(name) print(age) return#调用funcA函数funcA(age=30,name="python")funcA(name='python')dictionname(formal)def funcB(x,y,z,*args,**kwargs): print(x,y,z) print(args) print(kwargs)#funcB(1,2,3,4,5,6,a='hello',b=123,c={1,2,3})def add(a,b): #返回理工参数的和 total= a+b return total #print(total) 打印出None!?#调出用并输出点数 所有的练习题放在函数里面print(add(10,20))lt=[2,3,6,9,-20,8,0]for i in range(len(lt)-1): for j in range(len(lt)-i-1): if lt[j]lt[j+1]: lt[j],lt[j+1]=lt[j+1],lt[j] print(lt)lt=[1,22,13,6]bobble()def funcb(): if len(bb)>2: aa=bb[0:2] #这个地方很重要aa重新命名 其他可以写一致的末尾空号 # else: # lt print(aa)bb=[1,2,3,4,5]funcb()# # name=()# dt=[1,2,3,4,5]# dt1=[1,2,3,4,5]# if 1%2=1:# dt1[1:]# print(name)def func1(q): result = [] for i1 in range(len(q)): if i1 % 2 == 1: result.append(q[i1]) return resultr = func1([11, 22, 33, 44, 55])# [22, 44]print(r)def bbb(): new = [] for i in range(1,len(result)): if i%2==1: new.append(result[i]) print(new)result= [11,33,666,77,88,99] #[33, 77, 99]bbb() ####很经典的错误result=[]def bbb(): for i in range(len(result)): if i%2==1: result.append(result(i))a = lambda :'rongda'print(a())a =lambda y:y**2print(a(100))b= lambda z:z+2print(b(33))# dd= lambda xx:[i for i in x if i%2==0]# print(dd([1,2,3,4,5,6])) 打印错误 这两行sum_1 = lambda arg1,arg2:arg1+arg2print(sum_1(10,20))dd= lambda x:[i for i in x if i%2==0]print(dd([1,2,3,4,5,6]))def funA(x): return lambda y:x+ysum_1 = funA(10) #这里表示调用funA这个函数 sum_1=lamba y:10+yresult=sum_1(22)print(result)# 函数练习2"""def mylistfunc(lt): return [lt[i] for i in range(len(lt)) if i % 2 == 1]print(mylistfunc([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])) # [2, 4, 6, 8, 10]"""# 函数练习3def mylistfunc(**args): a = {i: args[i][0:2] for i in args if len(args[i]) > 2} return adic = {"k1": "python", "k2": [11, 33], "k3": '2', "k4": ['a', 'b', 'c']}print(mylistfunc(k1="python", k2=[11, 33], k3='2', k4=['a', 'b', 'c']))遍历循环for 很重要复习!!!for i in 'orange': print(i)name = {k1='banana',k2='orange',k3='apple'}name = {'k1':'banana','k2':'orange','k3':'apple'}name1 = (123,'apple',['apppe'])i=list(name.keys)for i,j in name.items(): print(i,j) for i,j in name.items(): print(i,j) for i in name: print(name[i])for i in range(len(name1)): print(name1[i])多重for循环的意义 纯计数for i in range(0,21): print(i) for j in range(30,35): print(j,end=" ") for h in range(60, 71): print(h, end=" ") print('结束','单挑')i=1j=0while i<6: print("a") #j=0 while j0:

    var -=1

    if var ==5 :

        continue

    print(var)

s =5

for s in range(15):

    s+=1

    if s ==10 :

        break

    print(s)

from sklearn.model_selection import validation_curve

test=%run

for  i in range(1,10):

    for j in range(1,i+1):

        #print("%d * %d =%d "%(i,j,i*j),end=" ")

        print("%d * %d =%d " % (i, j, i*j),end = " ")

    print(" ")

name='rongda'

password="123"

ss=0

while ss<=3:

    ss+=1

    name1 = input("请输入用户名:")

    password1=input("请输入密码:")

    if  name==name1 and password==password1:

        print("登陆成功")

        break

    else:

        print('输入错误,今天还有%d次机会'%(3-ss))

    if ss==3:

        print("输入超过最大次数请明天再来")

        break

'''