Python中的字母频率

Python中的字母频率

您可以使用翻译者配方来删除所有不在中的字符

alpha

。由于这样做使make

letters

中除了字符外仅包含其他字符

alpha

，因此它

n

是正确的分母。

然后，您可以使用a

collections.defaultdict(int)

来计数字母的出现：

import collectionsimport stringdef translator(frm='', to='', delete='', keep=None):    # Python Cookbook Recipe 1.9    # Chris Perkins, Raymond Hettinger    if len(to) == 1: to = to * len(frm)    trans = string.maketrans(frm, to)    if keep is not None:        allchars = string.maketrans('', '')        # delete is expanded to delete everything except        # what is mentioned in set(keep)-set(delete)        delete = allchars.translate(allchars, keep.translate(allchars, delete))    def translate(s):        return s.translate(trans, delete)    return translatealpha = 'abcdefghijklmnopqrstuvwxyz'keep_alpha=translator(keep=alpha)while True:    speech = raw_input("Enter file name:")    wholeFile = open(speech, 'r+').read()    lowlet = wholeFile.lower()    letters = keep_alpha(lowlet)    n = len(letters)    occurrences = collections.defaultdict(int)        for x in letters:        occurrences[x]+=1    for x in occurrences:        print x, occurrences[x], occurrences[x]/float(n)