// Calculate U_{1}/N = 1/N \sum_k \epsilon_h(k) f_h(\xi_h(k))
func HolonEnergy(env *tempAll.Environment) (float64, error) {
inner := func(k vec.Vector) float64 {
return env.Epsilon_h(k) * env.Fermi(env.Xi_h(k))
}
dim := 2
avg := bzone.Avg(env.PointsPerSide, dim, inner)
return avg, nil
}