python小知識學習
#!/usr/bin/env python
# -*- coding:UTF-8 -*-
#首先應該考慮程序所有可能出現的情況,然後總結各個規律,把大問題化成小問題
def power(x,n):
s=1
while(n>0):
s*=x
n-=1
return s
print(power(5,2))
#等下看下python的格式化輸出
def enroll(name,gender,age=6,city='Beijing'):
print('name:',name)
print('gender:',gender)
print('city:',city)
enroll('sarah','f')
enroll('abc',10,city='shanghai')
#注意默認參數也有坑
#可變參數 也是爲了解決在調用時候的問題,可以不用組裝成list或tuple
#例如計算a+b+c
def calc(numbers):
sum=0
for n in numbers:
sum+=n*n
return sum
calc([1,2,3])
def cals(*numbers):
cals(1,2,3)
#關鍵字參數,傳入的參數會自動組裝成dict
def person(name,age,**kw):
print('name:',name,'age:',age,'other:',kw)
person('bob',35,city='beijing')
person('bob',35,city='beijing',job='engineer')
關鍵字參數和可變參數一樣,可以先組裝成dict在以關鍵字的形式傳遞進去
>>> extra = {'city': 'Beijing', 'job': 'Engineer'}
>>> person('Jack', 24, city=extra['city'], job=extra['job'])
name: Jack age: 24 other: {'city': 'Beijing', 'job': 'Engineer'}
可以簡化爲下面的形式
>>> extra = {'city': 'Beijing', 'job': 'Engineer'}
>>> person('Jack', 24, **extra)
name: Jack age: 24 other: {'city': 'Beijing', 'job': 'Engineer'}