import numpy as np

def npy_to_fvecs(npy_file, fvecs_file):
    # 从npy文件中加载数组
    array = np.load(npy_file)
    data_to_fvecs(array, fvecs_file)

def data_to_fvecs(array, fvecs_file):
    # 打开fvecs文件进行写入
    with open(fvecs_file, 'wb') as f:
        # 获取数组的形状
        num_vectors, vector_dim = array.shape

        # 将每个向量写入fvecs文件
        for vector in array:
            # 向量的维度
            f.write(np.array(vector_dim, dtype=np.int32).tobytes())

            # 向量
            f.write(vector.astype(np.float32).tobytes())

    print("转换完成！")

# 调用函数进行转换
# npy_file = "input.npy"      # 输入的npy文件路径
# fvecs_file = "output.fevecs"
# npy_to_fvecs(npy_file, fvecs_file)

if __name__=='__main__':
    npy_file = '/tmp/test.npy'    # 输入的npy文件路径
    origin_file = "sift1m/sift_query.fvecs"  
    from sift1m.loading import fvecs_read
    dataset,_,_ = fvecs_read(origin_file)
    np.save(npy_file, dataset)
    fvecs_file = "/tmp/output.fevecs"
    npy_to_fvecs(npy_file, fvecs_file)