def _expm_multiply_interval_core_0(A, X, h, mu, m_star, s, q):
 for k in range(q):
  X[(k + 1)] = _expm_multiply_simple_core(A, X[k], h, mu, m_star, s)
 return (X, 0)

def _expm_multiply_interval_core_0 ( A , X , h , mu , m_star , s , q ) : for k in range ( q ) : X [ ( k + 1 ) ] = _expm_multiply_simple_core ( A , X [ k ] , h , mu , m_star , s ) return ( X , 0 )
a helper function .