from numpy import dot
from numpy.linalg import norm

cos_sim = dot(a, b)/(norm(a)*norm(b)) # 值越大越相似

或者

import numpy as np

def cosine_similarity(a, b):
    dot_product = np.dot(a, b)
    norm_a = np.linalg.norm(a)
    norm_b = np.linalg.norm(b)
    similarity = dot_product / (norm_a * norm_b)
    return similarity # 值越大越相似