将Ngram转换为Python中的频率字典

Question

有人能帮我把下面的ngram转换成下面的结果吗？返回应该连接ngram的前N-1个元素，并计算不同后继元素（第N个元素）出现的频率。我在考虑一些嵌套for循环，但我正在努力构建一个结构。非常感谢

ngrams = [['will', 'leave', 'florida'], ['will', 'leave', 'nyc'], ['will', 'leave', 'florida'],['wont', 'leave', 'florida']]

报税表应为：

{'will leave': {'florida': 2, 'nyc': 1}, 'wont leave': {'florida': 1}}

Answer 1

这里有一种方法

ngrams = [['will', 'leave', 'florida'], ['will', 'leave', 'nyc'], ['will', 'leave', 'florida'],['wont', 'leave', 'florida']]

dct = {'will leave': {}, 'wont leave': {}}

for i in ngrams:
    a, b, c = i
    if c in dct[a + ' ' + b]:
        dct[a+' '+b][c] += 1
    else:
        dct[a+' '+b].update({c: 1})

print(dct)

{'will leave': {'florida': 2, 'nyc': 1}, 'wont leave': {'florida': 1}}