I have a network containing about 2500 edges (directed) and I am looking at being able to work out all the routes downstream from a given beginning node.

Hm. What is your terminating condition?

A directed graph can contain loops:


a->b->c
   ^  |
   |  v
   e<-d

[download]

If your starting node is (a), when do you decide you've reach the (an) end?

Every time around the b->c->d->e->b loop, could be seen as another route. The only logical basis I can see for breaking that impasse is a rule along the lines of "Stop when there is no possibility of reaching a so far unvisited node. And that could be quite difficult to program efficiently.

As so often, more info required?

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^13: Finding All Paths From a Graph From a Given Source and End Node by BrowserUk
in thread Finding All Paths From a Graph From a Given Source and End Node by neversaint

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