eigenvalues of Laplacian (big network)

Hello. I am trying to calculate eigenvalues from a laplacian of a big network. Using laplacian_matrix is impossible, since the network is too big. I am using:
embed_laplacian_matrix(gUDUW,no=10) for an undirected graph and it works. But when I use
embed_laplacian_matrix(gUDUW,no=10,type=“OAP”) for a directed graph, I get NaN.

I have two questions: 1) What is the appropriate set of parameters for a directed network? and, 2) provided that I can solve the NaN problem, how can I tell the function to give me the eigenvalues of the laplacian in increasing order (from lambda_1=0 and on)?