英文词频统计预备，组合数据类型练习

Posted 2020-10-07 钟嘉丽

• 实例: 下载一首英文的歌词或文章，将所有,.？！等替换为空格，将所有大写转换为小写，统计某几个单词出现的次数，分隔出一个一个的单词。

  song=\'\'\'When I was dreaming about you baby
  You were dreaming of me
  Call me crazy
  Call me blind
  To still be suffering is stupid after all of this time
  Did I lose my love to someone better
  And does she love you like I do
  I do, you know I really really do
  Well hey
  So much I need to say
  Been lonely since the day
  The day you went away
  So sad but true
  For me there\'s only you
  Been crying since the day
  the day you went away
  I remember date and time
  September twenty second
  Sunday twenty five after nine
  In the doorway with your case
  No longer shouting at each other
  There were tears on our faces
  And we were letting go of something special
  Something we\'ll never have again
  I know, I guess I really really know
  Why do we never know what we\'ve got till it\'s gone
  How could I carry on the day you went away
  Cause I\'ve been missing you so much I have to say
  just one last dance\'\'\'
  songs=song.lower()
  song=song.replace(\',\',\' \')
  print(song)
  words=song.split(\' \')
  print(words)

• 

   

• 列表实例：由字符串创建一个作业评分列表，做增删改查询统计遍历操作。例如，查询第一个3分的下标，统计1分的同学有多少个，3分的同学有多少个等。

  ls=list(\'12134165135241335363\')
  for i in range (len(ls)):
      ls[i]=int(ls[i])
  print(ls)
  print(ls.index(3))
  print(ls.count(1))
  print(ls.count(3))

• 

   

• 简要描述列表与元组的异同。
• 答：列表和元组非常类似，有时候他们都干一样的事情。他们最大的区别是元组一旦被赋值，值不可以被改变，一旦改变就会出错；但是列表可以任意的更改。其次的区别是他们用不同的符号表示，复制的时候，列表用方括号[]，而元组用小括号（）。