# Talk:Flow network

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## Explanations

I think these points need more explanations:

See that there can be an edge from u to v in the residual network, even though there is no edge from u to v in the original network.

and

Notice that augmenting path (s,a,b,d,c,t) does not exist in the original network, but you can send flow along it, and still get a legal flow.

I would also suggest a simpler graphs (without the returning negative flows). It's just too complex for somebody who sees this for the first time. Such simpler graph is for example at Max flow. Maybe there could be both versions with explanation that they are equivalent. Jirka6 15:14, 23 February 2007 (UTC)

Ya I have also the same doubts in mind. This needs to be explained more.--Phoenixinsilico (talk) 16:04, 17 April 2010 (UTC)

## Skew symmetry

I have never heard that a flow must be skew symmetric and just checked my notes on maximum flow: "A flow satisfy the flow-conservation and the constraints 0 <= f(u,v) <= c(u,v)." A flow must not be skew symmetric but nonnegative. From where do you have your definition? --Zuphilip (talk) 09:37, 9 July 2008 (UTC)

I agree, this is not true. A network is a directed graph, i.e. you can have an edge (u,v) along with an edge (v,u), with different capacity etc., as opposed to an oriented graph ((v,u) in G implies (u,v) not in G). —Preceding unsigned comment added by 88.73.98.86 (talk) 11:28, 17 January 2010 (UTC)

## On flow conservation

The following was left at WP:VE/F, as Flow conservation redirects here I'm guessing this is the article in question. Thryduulf (talk) 17:51, 25 July 2013 (UTC)

Isn't it supposed to be the equation \sum_{u \in V} f(u, w) - \sum_{u \in V} f(w, u) = 0? Rodichi (talk) 16:13, 25 July 2013 (UTC)