Create signed graphs from adjacency matrices

`graph_from_adjacency_matrix_signed(A, mode = "undirected", ...)`

## Arguments

- A
square adjacency matrix of a signed graph

- mode
Character scalar, specifies how to interpret the supplied matrix. Possible values are: directed, undirected

- ...
additional parameters for `from_adjacency()`

## Value

a signed network as igraph object

## Examples

```
A <- matrix(c(0,1,-1,1,0,1,-1,1,0),3,3)
graph_from_adjacency_matrix_signed(A)
#> IGRAPH 81beff0 U--- 3 3 --
#> + attr: sign (e/n)
#> + edges from 81beff0:
#> [1] 1--2 1--3 2--3
```