python SVD分解

https://github.com/bwlewis/irlbpy

def calculate_sing_vec(A):
    try:
        import irlb
        # print('irlb package is installed for fast svd, using irlb')
        USV = irlb.irlb(A, 2)
    except ImportError:
        # print('No irlb package installed for fast svd, using numpy')
        USV = np.linalg.svd(A)
    first_sing_vec = USV[0][:, 0]
    return first_sing_vec