Java Library or algorithm for calculating coordinates of tree nodes / drawing
I am looking for a library which would give me the exact coordinates of each node in a tree (any tree, not just binary trees).
Let's say I define the tree in the following notation
(() (() (() () ()))
And some library gives me the coordinates like this:
[500 0]([200 50]() [600 50]([500 100]() [750 100]([600 150]() [700 150]() [800 150]()))
or any other notation which uniquely represents a tree.
This kind of library would enable a space-efficient drawing of trees and would also solve the problem of overlapping nodes and links. For example, if a tree is a list infact, I would like that library to take that into account and arrange nodes in a single column or row, to save space.
If nothing similar exists, an alg开发者_如何学Pythonorithm would also come in handy, provided that it can be implemented relatively easily.
I think the Nested Set model may help you.
The algorithm is fairly simple, and very efficient for reads, although updates to the tree are a little more expensive, because the boundaries of the nodes have to be updated in a cascading fashion. Here is the algorithm implemented in SQL.
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