hej there,
i don't no if i used the nearestNeighbour method of the STRtree wrong
but all i got were the same objects.
I looked at the code and saw something strange.
the method -> private Object[] nearestNeighbour(BoundablePair
initBndPair, double maxDistance) {... (line 328)
had the condition:
if (bndPair.isLeaves()) {
distanceLowerBound = currentDistance;
minPair = bndPair;
}
that means, if your pair are leaves the distanceLowerBound= 0 (!)
because it compares the first leave with itself -
and since its 0 the while-loop breaks because of (currentDistance >=
distanceLowerBound) (0=0).
The result is, you get your lowest distance with 0 and the same objects.
I guess there should be something added, like:
if (bndPair.isLeaves()) {
if(currentDistance > 0) //DON'T SAVE 0-DISTANCES
distanceLowerBound = currentDistance;
minPair = bndPair;
}
This way it doesn't save the 0 distance (Object distance with itself)
and you will get a proper result.
Since the code is quite old, i guess some people used the nearest
neighbour method before - so did i something wrong or was is it a bug?
(btw. is the jts project still alive?)
best regards,
bernd
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