Hi. I have implement Dijktsras algo too find shortest path in directed
weighted graph with positive edge weights.
Now trying to implement A* using a heuristic that is related to
geometric distance.
In my book it says to implement A* in same way as Dijkstra except for
changing the edge cost function in following way:
if
c : E ---> positive numbers
is original cost function from edges to positive numbers and f : V ---
> positive numbers
is an estimate of distance from nodes in graph to the goal node then
run Dijkstra with the following cost function
new_cost : E ---> positive numbers defined for edge e = (a,b) as
new_cost(e) = c(e) + f(b) - f(a).
Now if f is admissiable and is always lower bound for true cost then
this should work, but it dosnt. Do I need to change more ? So sum up:
Enough just to run Dijkstra and use new edge-cost when relaxing edges
without no other change ?
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