python实用小方法

一、创建随机字母

import random

# 创建随机字母
def make_code(n):
    res = ''
    for i in range(n):
        num = str(random.randint(1, 9))  # 随机选取1到9的一个整数
        letter = chr(random.randint(65, 90))  # 随机选大写英文的一个字母
        group = random.choice([num, letter])  # 随机选取整数还是大写字母
        res += group  # 循环次数加到空字符串中
    return res

print(make_code(4))

二、glob正则匹配出需要的文件

# 正则匹配出需要的文件
import glob

path = r"D:PycharmProjectsmapleface"
for name in glob.glob('{}*[0-9].*'.format(path)):
    print(name)
# 结果
# D:PycharmProjectsmaplefaceMyface1.jpg
# D:PycharmProjectsmaplefaceMyface2.jpg
# D:PycharmProjectsmaplefaceMyface3.jpg
# D:PycharmProjectsmaplefaceMyface4.jpg
# D:PycharmProjectsmaplefaceMyface5.jpg

# 匹配多种后缀名

res=glob.glob('{}*.*[xlsx|XLS]'.format(r"********"))
print(res)

三、判断元素是否为数字

import numpy as np
# 判断元素是否为数字
def is_number(s):
    try:
        if np.isnan(s) or s == False or s == True:
            return False
    except Exception:
        pass
    try:
        # 判断是否为浮点数
        float(s)
        return True
    except Exception:
        pass
    try:
        import unicodedata  # 处理ASCii码的包
        # 把一个表示数字的字符串转换为浮点数返回的函数
        unicodedata.numeric(s)
        return True
    except (TypeError, ValueError):
        pass
    return False


numbers = [12, "43", "地方", None, np.nan, 88.99, False, True]
print([is_number(i) for i in numbers])
# 结果
# [True, True, False, False, False, True, False, False]

五、格式化

# 格式化10进制
print(format(10,"b"))
# 格式化8进制
print(format(10,"o"))
# 格式化16进制
print(format(10,"x"))

六、精确处理数字

# 精确处理数字
a=1.1
b=3.2
print(a+b)

from decimal import Decimal
a=Decimal('1.1')
b=Decimal('3.2')
print(a+b)

七、正则匹配

# 正则匹配
import re
# 邮箱
res1='email1:378533872@qq.com email2:333312312@163.com eamil3:alexsb123@gmail.com'
res=re.findall('d+@w+.w+',res1)
print(res)
# 数字
res2="1-12*(60+(-40.35/5)-(-4*3))"
res=re.findall('(d+.d+|d+)',res2)
print(res)

八、flask-web

from aiohttp import web
async def index(request):
    return web.Response(text='Hello World')

async def api(request):
    data = await request.json()
    question = data['question']
    return web.json_response({"state":question})

app = web.Application()
app.add_routes([web.get('/', index),
                web.post('/api', api)])

if __name__ == '__main__':
    web.run_app(app, host='127.0.0.1', port=5000)

九、unicode转换

s="u4E1Cu65B9u8BC1u5238"
print(s.encode('unicode_escape').decode('unicode_escape'))
#东方证券

十、repr（）的应用

d=datetime.datetime(2020,1,2,0,0)
print(d)
#2020-01-02 00:00:00
print(repr(d)) #返回该对象名字的str
#datetime.datetime(2020, 1, 2, 0, 0)

十一、节假日判断

#安装pip install chinesecalendar

from chinese_calendar import is_holiday
today = datetime.datetime.now()
res=is_holiday(today)
print(res)

十二、判断中文

def is_Chinese(word):
    for ch in word:
        if 'u4e00' <= ch <= 'u9fff':
            return True
    return False


def is_number(word):
    res = re.search("^[0-9]*$", word)
    if res:
        return True
    return False

十三、判断文件的编码格式

import chardet

with open(r"*****","rb") as f:
    print (chardet.detect(f.read()))

十四、pip加速

pip install scrapy -i http://mirrors.aliyun.com/pypi/simple/ --trusted-host mirrors.aliyun.com

十五、生成随机ChromeAgent

import random

first_num = random.randint(55, 62)
third_num = random.randint(0, 3200)
fourth_num = random.randint(0, 140)

class FakeChromeAgent:
    os_type = [
                '(Windows NT 6.1; WOW64)', '(Windows NT 10.0; WOW64)', '(X11; Linux x86_64)',
                '(Macintosh; Intel Mac OS X 10_12_6)'
               ]

    chrome_version = 'Chrome/{}.0.{}.{}'.format(first_num, third_num, fourth_num)

    @classmethod
    def get_agent(cls):
        return ' '.join(['Mozilla/5.0', random.choice(cls.os_type), 'AppleWebKit/537.36',
                         '(KHTML, like Gecko)', cls.chrome_version, 'Safari/537.36']
                        )

print(FakeChromeAgent.get_agent())

十六、获取本地mac地址

import uuid

# 获取mac地址
addr_num = hex(uuid.getnode())[2:]
mac = "-".join(addr_num[i: i + 2] for i in range(0, len(addr_num), 2))
print(mac)

十七、流下载大文件

import requests

url = "http://wx4.sinaimg.cn/large/d030806aly1fq1vn8j0ajj21ho28bduy.jpg"
rsp = requests.get(url, stream=True)
with open('1.jpg', 'wb') as f:
    for i in rsp.iter_content(chunk_size=1024):  # 边下载边存硬盘, chunk_size 可以自由调整为可以更好地适合您的用例的数字
        f.write(i)

十八、redis有序集合实现权重取值

import redis

db_conn = redis.ConnectionPool(host="*.*.*.*", port=****, password="*****",db=0)
redis_clint = redis.Redis(connection_pool=db_conn, max_connections=10)

score=2 #分数值，数值越大，排序的时候越靠前
# 添加值
redis_clint.zadd("key_name", {"value001":score or 1})

# 大到小排序取值
res=redis_clint.zrevrange("key_name", 0, -1, withscores=False, score_cast_func=float)
value=res[0].decode()

# 判断数据是否存在，没有返回的None，有返回的是分数值
res=redis_clint.zscore("key_name",value)
print(res)

# 处理数据后，删除值
res=redis_clint.zrem("key_name",value)
print(res)