python函数
发布时间:2020-12-20 10:55:15 所属栏目:Python 来源:网络整理
导读:1.位置参数 位置参数就是普通的参数定义 def power(x): print(x**2) 2.默认参数 当调用函数时没有给参数值,那么会给使用定义的默认值。下面定义的函数可以定义参数值也可以不定义,不定义时x默认为9 def power(x = 3): print(x**2) 默认参数注意事项,当默
1.位置参数
def power(x): print(x**2) 2.默认参数
def power(x = 3): print(x**2)
In [1]: def power(L = []): ...: L.append(‘end‘) ...: return L ...: In [2]: In [2]: print(power()) [‘end‘] In [3]: print(power()) [‘end‘,‘end‘] In [4]: print(power()) [‘end‘,‘end‘,‘end‘] 3.可变参数
def sum(*num): temp = 0 for i in num: temp += i return temp print(sum(1,2,4,60)) L = [1,3,5,6] print(sum(*L)) 4.关键字参数
def person(name,age,**kw): print("name =",name,"age = ","kw = ",kw) person(‘fgnb‘,33,fg = ‘nb‘) extra = {‘1‘:‘1‘,‘2‘:"2",‘3‘:"3"} person(‘fgsb‘,‘33‘,**extra) 5.命名关键字参数
def person(name,*,a,b): print(name,b) def person(name,*args,city,job): #参数传递时需要2个位置参数,city和job的关键字参数和任意个参数变量 print(name,args,job) person(‘fg‘,32,a = ‘a‘,b = ‘b‘) 6.参数的顺序
def f1(a,b,c=0,**kw): print(‘a =‘,‘b =‘,‘c =‘,c,‘args =‘,‘kw =‘,kw) def f2(a,d,‘d =‘,kw) >>> f1(1,2) a = 1 b = 2 c = 0 args = () kw = {} >>> f1(1,c=3) a = 1 b = 2 c = 3 args = () kw = {} >>> f1(1,‘a‘,‘b‘) a = 1 b = 2 c = 3 args = (‘a‘,‘b‘) kw = {} >>> f1(1,‘b‘,x=99) a = 1 b = 2 c = 3 args = (‘a‘,‘b‘) kw = {‘x‘: 99} >>> f2(1,d=99,ext=None) a = 1 b = 2 c = 0 d = 99 kw = {‘ext‘: None} # 可以通过List或者tuple传递参数 >>> args = (1,4) >>> kw = {‘d‘: 99,‘x‘: ‘#‘} >>> f1(*args,**kw) a = 1 b = 2 c = 3 args = (4,) kw = {‘d‘: 99,‘x‘: ‘#‘} >>> args = (1,3) >>> kw = {‘d‘: 88,‘x‘: ‘#‘} >>> f2(*args,**kw) a = 1 b = 2 c = 3 d = 88 kw = {‘x‘: ‘#‘} (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |