code: def matrix(self):
          
          n = self.v.shape[0]
          return numpy.eye(n, n) - self.beta * numpy.dot(self.v, self.v.T.conj())
docs: Build matrix representation of Householder transformation.
  
          Builds the matrix representation
          :math:`H = I - \\beta vv^*`.
  
          **Use with care!** This routine may be helpful for testing purposes but
          should not be used in production codes for high dimensions since
          the resulting matrix is dense.