python.matrix.getA()

in the Logistic regression method:
weights.getA(): a method in numpy

website:
https://docs.scipy.org/doc/numpy/reference/generated/numpy.matrix.getA.html

• numpy.matrix.getA

  matrix.getA()[source] Return self as an ndarray object.

  Equivalent to np.asarray(self).

  Parameters: None Returns: ret : ndarray self as an ndarray

作用是把矩阵转成一个ndarray.
如果不转，矩阵的每个元素将无法取出，会造成越界的问题。