Hi!

I’m using python-igraph to perform graph subsetting/projection on directed graphs, and I was using .select on EdgeSeq to pull out edges of interest.

I found that when using the _incident as the condition, it seems to return equivalent statements to _source_in, which doesn’t seem consistent with my understanding of incidence.

Is this expected, or is this a bug?

And in either case, how should I work around this (I’m assuming using .incidence on each vertex of interest?)

Basic example:

```
import igraph as ig
edgelist = [
(0, 1),
(1, 2),
(2, 3),
]
G = ig.Graph(edgelist, directed=True)
subset_edges = G.es.select(_incident_eq=(1,))
print(len(subset_edges))
print([(edge.source, edge.target) for edge in subset_edges])
```

Expected Output:

```
2
[(0, 1), (1, 2)]
```

Actual Output:

```
1
[(1, 2)]
```

Thank you in advance.

EDIT:

This is on iGraph 0.10.5