1,print('linking'),print(133) true
print('linking'+12332) flase
2True不是true
True是其他非0的正整数字,flase是0
3python 数组下标
a=range(10)
while a:
print(a[-2])
a=a[:len(a)-1]
4python使用缩进实现block,循环后面记得加上:
example_list=[1,23,6,56456,48,564,6354,684,]
for i in example_list:
print(i)
print('rilegoule')
print('end!!!!!!!!!!!!!!!!!!!')
5,python的一些常见函数
range(start,end,step)
zip(a,b):ab2个list合并
6,python的四种集合
tuple:a_tuple = (12, 3, 5, 15 , 6),一连串有顺序的数字
list:a_list = [12, 3, 67, 7, 82],列表是一系列有序的数列
a=[1,2,3,4,2]
print(a[0])
print(a[-1])
print(a[0:3])
print(a[3:])
print(a[-3:])
print(a.index(2))
print(a.count(2))
a.sort()
print(a)
a.sort(reverse=True)
print(a)
dict:key-value.无序
,set
7一个python文件中的结构,class,def,变量在那些地方
8为什么不报错?
x='a'
y=2
z=3
if xwrite-->close
open -->file.read()
14 class与def,none是哪里的
class Classmates:
name='lijun'
age='24'
def add(self,x,y):
print(self.name)
result=x+y
print(result)
def times(self,x,y):
print(self.name)
result=x*y
print(result)
cal=Classmates()
print(cal.name)
print(cal.add(10,10))import time
print(time.localtime())
import time as t
print(t.localtime())
from time import time,localtime
print(localtime())
print(time())
from time import *
print(localtime())
print(cal.times(10,10))
lijun
lijun
20
None
15
lijun
100
None
15,__init__,初始化对象的,构造函数
class Calculator:
name='good calculator'
price=18
def __init__(self,name,price,hight=10,width=14,a=[1,2,3,4,2]
print(a[0])
print(a[-1])
print(a[0:3])
print(a[3:])
print(a[-3:])
print(a.index(2))
print(a.count(2))
a.sort()
print(a)
a.sort(reverse=True)
print(a)
weight=16):
self.name=name
self.price=price
self.h=hight
self.wi=width
self.we=weight
c=Calculator('bad',18)
print(c.h,c.wi,c.h,c.name,c.price)
16,input读取数据
socre=int(input('plase send me your grade'))
if socre>=90:
print('a')
if 60<=socre<90:
print('b')
else:
print('you are go out')
17,导包的模式
import time
print(time.localtime())
import time as t
print(t.localtime())
from time import time,localtime
print(localtime())
print(time())
from time import *
print(localtime())
18,异常处理
try:
file=open('eeee.txt','r')
except Exception as e:
print(e)
19,lambda
fun= lambda x,y:x+y
#这里要定义int整数,否则会默认为字符串
x=int(input('x='))
y=int(input('y='))
print(fun(x,y))
20.python的深copy与浅copy.
import copy
a=[1,2,3]
id(a)#显示a的内存地址
c=copy.copy(a)#与a内存地址不一样,只是值
d=copy.deepcopy(a)#与a内存地址一样```