'''
一.python之基
'''
# 1.求绝对值
print(abs(-6))# 2.元素都为真
print(all([1, 0, 3, 5]))
print(all([1, 2, 3, 4]))# 3.元素至少一个为真
print(any([0, 0, 0, []]))
print(any([0, 0, 1]))# 4.十进制->二进制
print(bin(10))
# 5.十进制->八进制
print(oct(10))
# 6.十进制->十六进制
print(hex(10))# 7.判断是真是假(测试一个对象是真还是假）
print(bool([0, 0, 0]))
print(bool([]))
print(bool([1, 0, 1]))# 8.字符串转字节
s = 'apple'
print(bytes(s, encoding='utf-8'))# 9.将字符，数值类型转换为字符串类型
integ = 100
print(str(integ))# 10.判断对象能否被调用
print(callable(str))
print(callable(int))#11.十进制转ascii
print(chr(65))#12.ascill转十进制
print(ord('a'))#13.执行字符串代表的代码
s='print("hello")'
r=compile(s,"<string>","exec")
print(r)
print(exec(r))#14.创建复数
print(complex(1,2))#15.创建数据字典
'''
>>> dict()
{}
>>> dict(a='a',b='b')
{'a': 'a', 'b': 'b'}
>>> dict(zip(['a','b'],[1,2]))
{'a': 1, 'b': 2}
>>> dict([('a',1),('b',2)])
{'a': 1, 'b': 2}
'''#16.取商和余数
'''
>>> divmod(10,3)
(3, 1)
'''#17.枚举对象
'''
>>> s=["a","b","c"]
>>> for i,v in enumerate(s,1):print(i,v)
1 a
2 b
3 c
'''#18.计算表达式
'''
>>> s="1+3+5"
>>> eval(s)
9
'''#19.过滤器
'''
>>> fil=filter(lambda x:x>10,[1,2,3,12,23,41])
>>> list(fil)
[12, 23, 41]
'''#20.将字符串或整数装换为浮点数
'''
>>> float(3)
3.0
'''#21.字符串格式化
'''>>> print("{:+.2f}".format(-1))                      带符号位保留2位小数
-1.00
>>> print("{:.2%}".format(0.25))                     百分比格式
25.00%
>>> print("i am {0},age{1}".format("tom",18))        格式化输出
i am tom,age18
>>> print("{:.2e}".format(10000000000))              指数计法
1.00e+10
>>> print("{:>10d}".format(10))                      右对齐10
>>> print("{:<10d}".format(10))                      左对齐
10        
>>> print("{:^10d}".format(10))                      中间对齐10  
'''#22.创建一个不可修改的集合
'''
>>> frozenset([1,1,3,2,3])
frozenset({1, 2, 3})
'''#23.创建迭代器类型
'''
>> > lst = [1, 3, 5]
>> > for i in iter(lst):print(i)
1
3
5
'''#24.转列表类型
'''
>>> list(map(lambda x:x%2==1,[1,3,4,2,5,2]))
[True, True, False, False, True, False]
>>> list(map(lambda x,y:x%2==1 and y%2==0,[1,2,3,4],[2,3,4]))
[True, False, True]
'''#25.下一个元素
'''
>>> it=iter([1,2,3,4,5])
>>> next(it)
1
>>> next(it)
2
'''#26.打开文件
'''
>>> fo=open("/Users/zhengyan/Desktop/python/爬虫/1.txt",mode='r',encoding='utf-8')
>>> fo.read()
'Zhejiushi ai \n''''#27.次幂
'''
>>> pow(3,2)
9
'''#28.反向迭代器
'''
>>> rev=reversed([1,2,3,4,5])
>>> for i in rev:print(i)
5
4
3
2
1
'''#29.四舍五入保留小数位
'''
>>> round(2.123213,3)
2.123
>>> round(10.05,1)
10.1
'''#30.转为集合类型（实现去重）
'''
>>> a=[1,2,3,2,1]
>>> set(a)
{1, 2, 3}
'''#31.转为切片类型 -> range(start,stop,step)
'''
>>> a=[1,2,3,4]
>>> a[slice(0,3,1)]
[1, 2, 3]
'''#32.排序函数
'''
>>> a=[2,1,4,2,6,4]
>>> sorted(a,reverse=True)
[6, 4, 4, 2, 2, 1]
'''#33.求和函数
'''
>>> a=[1,2,3,4]
>>> sum(a)
10
>>> sum(a,10)
20
'''#34.转元组（不可变的序列）
'''
>>> list=[1,3,4]
>>> I_tuple=tuple(list)
>>> I_tuple
(1, 3, 4)
'''#35.聚合迭代器
'''
x=[1,2,3]
y=[2,3,4]
print(list(zip(x,y)))a=range(5)
b=list('abcde')
print([str(y)+str(x)for x,y in zip(a,b)])
''''''
二.python之正
'''
import  re#1.查找第一个匹配词
'''
>>> s='I love pqh very much'
>>> r=re.search('pqh',s)
>>> r.span()
(7, 10)
'''#2.查找所有1
'''
>>> s='I love pqh very much 1314'
>>> r=re.finditer('1',s)
>>> for i in r:print(i)
<re.Match object; span=(21, 22), match='1'>
<re.Match object; span=(23, 24), match='1'>
'''#3.匹配数字【0-9】
'''
>>> s = '一共20行代码运行时间13.59s' 
>>> pat=r'\d+'                  #+表示匹配数字(\d表示数字的通用字符)1次或多次
>>> r=re.findall(pat,s)
>>> print(r)
['20', '13', '59']
'''#4.?表示前一个字符匹配0或1次
'''
>>> s = '一共20行代码运行时间13.59s'
>>> pat=r'\d+\.?\d+'        # ?表示匹配小数点(\.)0次或1次
>>> r=re.findall(pat,s)
>>> print(r)
['20', '13.59']
'''#5.^匹配字符串的开头
'''
>>> s = 'This module provides regular expression matching operations similar to those found in Perl'
>>> pat=r'^[emrt]'
>>> r=re.findall(pat,s)
>>> print(s)
This module provides regular expression matching operations similar to those found in Perl
'''#6.re.l忽略大小写
'''
s = 'This module provides regular expression matching operations similar to those found in Perl'
pat = r'^[emrt]'
r = re.compile(pat,re.I).search(s)
print(r)
'''#7.使用正则提取单词
'''
>>> s = 'This module provides regular expression matching operations similar to those found in Perl'
>>> pat=r'\s?[a-zA-Z]+'
>>> r=re.findall(pat,s)
>>> print(r)
[' module', ' provides', ' regular', ' expression', ' matching', ' operations', ' similar', ' to', ' those', ' found', ' in', ' Perl']'''#8.使用split函数直接分割单词
'''
>>> s = 'This module provides regular expression matching operations similar to those found in Perl'
>>> pat=r'\s+'
>>> r=re.split(pat,s)
>>> print(r)
['This', 'module', 'provides', 'regular', 'expression', 'matching', 'operations', 'similar', 'to', 'those', 'found', 'in', 'Perl']
'''#9.提取以m或t开头的单词，忽略大小写
'''
>>> s = 'This module provides regular expression matching operations similar to those found in Perl'
>>> pat=r'\s?([mt][a-zA-Z]*)'
>>> r=re.findall(pat,s)
>>> print(r)
['module', 'matching', 'tions', 'milar', 'to', 'those']'''#10.使用^查找字符串开头的单词
'''
>>> s = 'This module provides regular expression matching operations similar to those found in Perl'
>>> pat=r'^([mt][a-zA-Z]*)\s'
>>> r=re.compile(pat,re.I).findall(s)
>>> print(r)
['This']
'''#11.使用match匹配单词
'''
>>> s = 'This module provides regular expression matching operations similar to those found in Perl'
>>> pat=r'\s+'
>>> r=re.split(pat,s)
>>> res=[i for i in r if re.match(r'[mMtT]',i)]
>>> print(res)
['This', 'module', 'matching', 'to', 'those']
'''#12.贪心匹配
'''
>>> content='<h>ddedadsad</h><div>graph</div>bb<div>math</div>cc'
>>> pat=re.compile(r"<div>(.*)</div>")
>>> m=pat.findall(content)
>>> print(m)
['graph</div>bb<div>math']
'''#13.非贪心匹配
'''
>>> content='<h>ddedadsad</h><div>graph</div>bb<div>math</div>cc'
>>> pat=re.compile(r"<div>(.*?)</div>")
>>> m=pat.findall(content)
>>> print(m)
['graph', 'math']
'''#14.含有多种分割符
'''
>>> content = 'graph math,,english;chemistry'
>>> pat=re.compile(r"[\s\,\;]+")
>>> m=pat.split(content)
>>> print(m)
['graph', 'math', 'english', 'chemistry']
'''#15.替换匹配的子串
'''
>>> content="hello 12345, hello 456321"
>>> pat=re.compile(r'\d+')
>>> m=pat.sub("666",content)
>>> print(m)
hello 666, hello 666
'''#16.爬取百度首页标题
'''
import re
from urllib import request
data=request.urlopen("http://www.baidu.com/").read().decode()
pat=r'<title>(.*?)</title>'
result=re.search(pat,data)
print(result)
'''#19.常用元字符总结
'''
. 匹配任意字符 
^ 匹配字符串始位置 
$ 匹配字符串中结束的位置 
* 前面的原子重复0次1次多次 
? 前面的原子重复一次或者0次 
+ 前面的原子重复一次或多次 
{n} 前面的原子出现了 n 次 
{n,} 前面的原子至少出现 n 次 
{n,m} 前面的原子出现次数介于 n-m 之间 
( ) 分组,需要输出的部分
'''#20.常用通用字符总结
'''
\s 匹配空白字符 
\w 匹配任意字母/数字/下划线 
\W 和小写 w 相反，匹配任意字母/数字/下划线以外的字符 
\d 匹配十进制数字 
\D 匹配除了十进制数以外的值 
[0-9] 匹配一个0-9之间的数字 
[a-z] 匹配小写英文字母 
[A-Z] 匹配大写英文字母''''''
三.python之例
'''
#1.链式比较
'''
>>> i=3
>>> print(1<i<3)
False
>>> print(1<i<=3)
True
'''#2.不用else和if实现计算器
'''
from operator import  *def calculator(a,b,k):return{'+':add,'-':sub,'*':mul,'/':truediv,'**':pow}[k](a,b)print(calculator(1,2,'+'))
print(calculator(1,2,'**'))
'''#3.链式操作
'''
from operator import (add,sub)def add_or_sub(a,b,oper):return (add if oper=='+' else sub)(a,b)print(add_or_sub(1,2,'-'))
'''#4.求字符串的字节长度
'''
def str_byte_len(mystr):return(len(mystr.encode('utf-8')))
print(str_byte_len('i love pqh'))
print(str_byte_len('字符'))
'''#5.寻找第n次出现位置
'''
def search_n(s,c,n):size=0for i,x in enumerate(s):if x==c:size+=1if size==n:return ireturn -1
print(search_n("fasdqdsacsaw",'a',3))
print(search_n("dsadsawdsawd",'a',100))
'''#6.去掉最高分，最低分求平均
'''
def score_mean(lst):lst.sort()lst_2=lst[1:(len(lst)-1)]return round(sum(lst_2)/len(lst_2),1)
lst=[9.1,9.0,8.1, 9.7, 19,8.2, 8.6,9.8]
print(score_mean(lst))def score_mean1(lst):lst.remove(min(lst))lst.remove(max(lst))return round(sum(lst)/len(lst),1)
print(score_mean1(lst))
'''#7.交换两元素
'''
def swap(a,b):return b,a
print(swap(1,2))
'''#8.两两组队
'''
import numpy as np
x,y=np.mgrid[0:5,0:5]
a=list(map(lambda xe,ye:[(ex,ey)for ex,ey in zip(xe,ye)],x,y))
print(a)
'''#9.打印99乘法表
'''
for i in range(1,10):for j in range(1,i+1):print("{0}*{1}={2}".format(j,i,j*i),end='\t')print()
'''#10.嵌套数组完全展开
'''
from collections.abc import *def flatten(input_arr,output_arr=None):if output_arr is None:output_arr=[]for ele in input_arr:if isinstance(ele,Iterable):  #判断ele是否可以迭代flatten(ele,output_arr)else:output_arr.append(ele)return output_arr
print(flatten(([[[1,2,3],[4,5,6]]])))import numpy as np
b=np.array([[1,3,4],[2,3,5]])
print(b.flatten())
'''#11.列表等分
'''
from math import ceil
def divide(lst,size):if size<=0:return [lst]return [lst[size*i:size*(i+1)] for i in range(0,ceil(len(lst)/size))]
print(divide([1,3,5,6,7],3))
'''#12.斐波那契数列
'''
def finbonaqie(n):a,b=1,1for _ in range(n):yield aa,b=b,a+b
print(list(finbonaqie(3)))
'''#13.过滤掉空值
'''
def filter_false(lst):return list(filter(bool,lst))
r=filter_false([None,0,False,'',[],'ok',[1,2]])
print(r)
'''#14.返回更长列表
'''
def max_length(*lst):return max(*lst,key=lambda v:len(v))
r=max_length([1,2,3],[4,5,6,7],[8])
print(r)
'''#15.出现次数最多的元素
'''
def max_frequency(lst):return max(lst,default='列表为空',key=lambda v:lst.count(v))
lst=[1,3,4,2,5,32,1,52,1]
r=max_frequency(lst)
print(r)
'''#16.多个列表的最大值
'''
def max_list(*lst):return max(max(*lst,key=lambda x:max(x)))
r=max_list([1,2,3],[6,7,8],[4,5])
print(r)
'''#17.检查list是否有重复元素
'''
def has_duplicates(lst):return len(lst)==len(set(lst))
print(has_duplicates([1,2,1,2,23]))
'''#18.多个列表的最小值
'''
def min_list(*lst):return  min(min(*lst,key=lambda v:min(v)))
print(min_list([1,2,3],[6,7,8],[4,5]))
'''#19.找出所有重复的元素
'''
from collections import Counter
def find_all_duplicates(lst):c=Counter(lst)print(c)return list(filter(lambda k:c[k]>1,c))
print(find_all_duplicates([1,2,2,3,4,3,4]))
'''#20.列表反转
'''
def reverse(lst):return lst[::-1]
print(reverse([1,2,3,4]))
'''#22.浮点数等差数列
'''
def rang(start,stop,n):start,stop,n=float('%.2f'%start),float('%.2f'%stop),float('%.2f'%n)step=(stop-start)/nlst=[start]while n>0:start,n=start+step,n-1lst.append(round((start),2))return lst
print(rang(1,8,10))
'''#23.按条件分组
'''
def bof_by(lst,fn):return [[x for x in lst if fn(x)],[x for x in lst if not fn(x)]]
records=[25,12,53,754,1]
print(bof_by(records,lambda x:x>50))
'''#24.map实现向量运算
'''
lst1=[1,2,3,4,5,6]
lst2=[3,4,5,5,5,6]
print(list(map(lambda x,y:x*y+1,lst1,lst2)))'''#25.联合统计次数（Counter）
'''
from collections import Counter
a = ['apple', 'orange', 'computer', 'orange']
b = ['computer', 'orange']
ca=Counter(a)
cb=Counter(b)
print(ca+cb)'''#26.值最大的键值对
'''
def max_pairs(dic):if len(dic)==0:return dicmax_val=max(map(lambda x:x[1],dic.items()))return [item for item in dic.items() if item[1]==max_val]
print(max_pairs({'a':-10,"b":-2}))
'''#27,合并两个字典
'''
dic1={'a':1,'b':2}
dic={'c':3,'d':4}
def hebin(dic1,dic2):return {**dic1,**dic2}
print(hebin(dic1,dic))'''#28.返回字典前n个最大值对于的键
'''
from heapq import nlargest
def topdict(d,n):return nlargest(n,d,key=lambda k:d[k])
print(topdict({'a': 10, 'b': 8, 'c': 9, 'd': 10}, 3))
'''#29.最小字典
'''
d={'a':-10,'b':2}
print(min(d.items(),key=lambda x:x[1]))'''#30.反转字符串
'''
st='pqh'
print(''.join(reversed(st)))
print(st[::-1])
'''