'random variable
Parameters
size : int or tuple
the number and shape of random variables to draw.
Returns
rvs : ndarray
the returned random variables with shape given by size and the
dimension of the multivariate random vector as additional last
dimension
Notes
uses numpy.random.multivariate_normal directly'

def rvs(self, size=1):

    return np.random.multivariate_normal(self.mean, self.cov, size=size)
