我有一个文件,其中包含乐队列表以及专辑的制作年份。 我需要编写一个函数来查看这个文件,并找出这些乐队的不同名称,并计算出这些乐队在这个文件中出现的次数。用某些词汇打印每个短语/单词的频率?
文件的样子是这样的:
Beatles - Revolver (1966)
Nirvana - Nevermind (1991)
Beatles - Sgt Pepper's Lonely Hearts Club Band (1967)
U2 - The Joshua Tree (1987)
Beatles - The Beatles (1968)
Beatles - Abbey Road (1969)
Guns N' Roses - Appetite For Destruction (1987)
Radiohead - Ok Computer (1997)
Led Zeppelin - Led Zeppelin 4 (1971)
U2 - Achtung Baby (1991)
Pink Floyd - Dark Side Of The Moon (1973)
Michael Jackson -Thriller (1982)
Rolling Stones - Exile On Main Street (1972)
Clash - London Calling (1979)
U2 - All That You Can't Leave Behind (2000)
Weezer - Pinkerton (1996)
Radiohead - The Bends (1995)
Smashing Pumpkins - Mellon Collie And The Infinite Sadness (1995)
.
.
.
输出必须是在按频率的降序,看起来像这样:
band1: number1
band2: number2
band3: number3
这里是我到目前为止的代码:
def read_albums(filename) :
file = open("albums.txt", "r")
bands = {}
for line in file :
words = line.split()
for word in words:
if word in '-' :
del(words[words.index(word):])
string1 = ""
for i in words :
list1 = []
string1 = string1 + i + " "
list1.append(string1)
for k in list1 :
if (k in bands) :
bands[k] = bands[k] +1
else :
bands[k] = 1
for word in bands :
frequency = bands[word]
print(word + ":", len(bands))
我认为有一个更简单的方法来做到这一点,但我不确定。另外,我不确定如何按频率对字典进行排序,是否需要将其转换为列表?
查看['collections.Counter'](http://docs.python.org/2/library/collections.html#collections。计数器) –