This function computes the Fréchet variance using exclusively inter-point
distances. As such, it can accommodate any pair of representation and
distance.

`var2_nvd(x, representation = "adjacency", distance = "frobenius")`

## Arguments

- x
An `nvd`

object listing a sample of networks.

- representation
A string specifying the graph representation to be
used. Choices are adjacency, laplacian, modularity, graphon. Default is
adjacency.

- distance
A string specifying the distance to be used. Possible choices
are: hamming, frobenius, spectral or root-euclidean. Default is frobenius.

## Value

A positive scalar value evaluating the variance based on inter-point
distances.

## Examples

```
gnp_params <- list(p = 1/3)
x <- nvd(model = "gnp", n = 10L, model_params = gnp_params)
var2_nvd(x = x, representation = "graphon", distance = "frobenius")
#> [1] 29.14793
```