Filtered graph: node and edge filters #45
Description
Now that we are starting to implement graph traversal e.g. with
- Adds depth-first search and breadth-first search #40
- Shortest path with a base line Dijkstra implementation #44
there's a need for working on "filtered" graphs where nodes or edges can be marked and left out.
There are various design decisions to take
- Should edge and node filters be simple dense bitmasks to mask out edges and nodes
- Should we provide instead a filter function the user can pass to algorithms to decide if an edge or node should be traversed
- How do we implement this within our existing graph framework, meaning in APIs and structs and functions
Looking a bit into the future once we have #41 we can build our succinct graph. Ideally we'll then provide the very same graph operations and traversals there. How do we get these three into a single API: csr graph we have right now, succinct graph, filtered graph? Is there a way to abstract over the implementations and stay with a single API?