That's tricky: In terms of assignment, if G.Edges(i, :) is assigned to, the graph class interprets this as assigning to all elements, including EndNodes, even if that property is not modified.
One approach would be to only open the properties of the edge in the variable editor, but not the first variable EndNodes:
>> openvar('G.Edges(1350,2:end)')
This will allow the value to be changed, but of course it will not display which edge is currently being changed.
You might provide some of that information in a bit of a roundabout fashion like this:
>> edge_1_3 = 4;
>> openvar('G.Edges(edge_1_3, 2:end)')
The variable name of the index into the edges is displayed at the top of the variable editor, which could be some indication to your user of which edge is currently being shown.
