Using Laplacians to find fiedler values

@danspielman I am trying to find the fiedler value for a directed graph using fiedler command in Laplacians package in Julia.

using LightGraphs
using Laplacians

g=watts_strogatz(100,12,0.0,is_directed=true)
a=adjacency_matrix(g)
l=fiedler(a; nev=1, tol=0.0)

However, I get the following error:

ERROR: InexactError: Int64(0.8333333333333334)

It seems that the fiedler function requires a matrix of Floats.
You could construct one instead writing
a = Float64.(adjacency_matrix(g))

1 Like

that’s worth submitting a PR for :).

If any other issues come up we should see how they are computing the laplacian.

Not necessarily the most related, but my brain is completely dead. Can the Laplacians package be used to solve the Laplace/Poisson equations (i.e. https://en.wikipedia.org/wiki/Poisson's_equation) or is that an entirely different beast?