I am looking for C# code to construct an r-tree. I have code that builds an r-tree incrementally i.e. items are added one by one to the tree, but I guess a better r-tree could be built if all items are given all at once to the tree creation algorithm. Please let me know if anyone knows how to bulk-load an r-tree in this manner. I tried doing some search but couldn't find anything very useful.
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The most common method for low-dimensional point data is sort-tile-recursive (STR). It does exactly that: sort the data, tile it into the optimal number of slices, then recurse if necessary.
The leaf level of a STR-loaded tree with point data will have no overlap, so it is really good. Higher levels may have overlap, as STR does not take the extend of objects into account.
A proven good bulk-loading is a key component to the Priority-R-Tree, too.
And even when not bulk-loading, the insertion strategy makes a big difference. R-Trees built with linear splits such as Guttmans or Ang-Tan will usually be worse than those built with the R*-Tree split heuristics. In particular Ang-Tan tends to produce "sliced" pages, that are very unbalanced in their spatial extend. It is a fast split strategy and probably the simplest, but the results aren't good.
Has QUIT--Anony-Mousse
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Would please provide a (reference to) step by step description? Thanks – Kaveh Shahbazian Dec 09 '12 at 14:56
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Google for "Sort Tile Recursive". It's all over the interwebz. – Has QUIT--Anony-Mousse Dec 09 '12 at 15:58
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A paper by Achakeev et al.,Sort-based Parallel Loading of R-trees might be of some help. And you could also find other methods in their references.
gongzhitaao
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