python - 如何包装 numpy 数组类型？

Question

我想创建一个扩展 numpy 数组基类型的类，

class LemmaMatrix(numpy.ndarray):
    @classmethod
    def init_from_corpus(cls, ...): cls(numpy.empty(...))

但显然，它不允许多维数组类型。有没有解决的办法？提前致谢!

ndarray(empty([3, 3]))
TypeError: only length-1 arrays can be converted to Python scalars

Answer 1

import numpy as np
class LemmaMatrix(np.ndarray):
    def __new__(subtype,data,dtype=None):
        subarr=np.empty(data,dtype=dtype)
        return subarr

lm=LemmaMatrix([3,3])
print(lm)
# [[  3.15913337e-260   4.94951870e+173   4.88364603e-309]
#  [  1.63321355e-301   4.80218258e-309   2.05227026e-287]
#  [  2.10277051e-309   2.07088188e+289   7.29366696e-304]]

您可能还想阅读 this guide有关如何子类化 ndarray 的更多信息。