美文网首页
日常练习(10题)

日常练习(10题)

作者: wangcc_sd | 来源:发表于2019-04-16 15:29 被阅读0次

    1.有一个jsonline格式的文件file.txt大小约为10K

    def get_lines():
        with open('file.txt','rb') as f:
            return f.readlines()
    
    if __name__ == '__main__':
        for e in get_lines():
            process(e) # 处理每一行数据
    '''
    

    解 使用readlines

    # bufsize = 65536
    # with open(path) as  infile:
    #     while True
    #         lines=infile.readlines(bufsize)
    #         if not lines:
    #             pass
    #         for line in lines:
    #             process(line)
    

    解法2

    # import  mmap
    # with open(path) as infile:
    #     m = mmap.mmap(infile, 0, access=mmap.ACCESS_READ)
    '''
    

    3.输入日期, 判断这一天是这一年的第几天?

    '''
    # import datetime
    # # def dayofyear():
    # #     year = input("yesr")
    # #     month = input("month")
    # #     day = input("day")
    # #     date1 = datetime.date(year=int(year), month=int(month), day=int(day))
    # #     date2 = datetime.date(year=int(year), month=1, day=1)
    # #     return (date1 - date2).days+1
    # #
    # # print(dayofyear())
    
    '''
    

    4.打乱一个排好序的list对象alist?

    '''
    # import random
    # alist=[1,2,3,4,5,6]
    # random.shuffle(alist)
    # print(alist)
    '''
    

    5.现有字典 d= {'a':24,'g':52,'i':12,'k':33}请按value值进行排序?

    '''
    # d = {'a': 24, 'g': 52, 'i': 12, 'k': 33}
    # a=sorted(d.items(),key=lambda x:x[1])
    # print(a)
    
    '''
    

    6.字典推导式

    d = {key:value for (key,value) in iterable}
    

    7.请反转字符串 "aStr"?

    '''
    #print('aStr'[::-1])
    '''
    

    8.将字符串 "k:1 |k1:2|k2:3|k3:4",处理成字典 {k:1,k1:2,...}

    '''
    # str1 = "k:1|k1:2|k2:3|k3:4"
    # def strdict(str1):
    #     dict1={}
    #     for items in str1.split('|'):
    #         key,value=items.split(":")
    #         dict1[key]=value
    #     return dict1
    # a=strdict(str1)
    # print(a)
    '''
    

    9.请按alist中元素的age由大到小排序

    '''
    # alist = [{'name':'a','age':20},{'name':'b','age':30},{'name':'c','age':25}]
    # # def sort_by_age(list1):
    # #     return sorted(alist,key=lambda x:x['age'],reverse=True)
    # # print(sort_by_age(alist))
    '''
    

    10.下面代码的输出结果将是什么?

    '''
    list = ['a','b','c','d','e']
    print(list[10:])
    #返回空列表
    

    相关文章

      网友评论

          本文标题:日常练习(10题)

          本文链接:https://www.haomeiwen.com/subject/yjmbwqtx.html