Hi Alex, > 'idx' is deliberately designed in this way. It does only the basic, > straight-forward binary tree operations. This can be quite fast, > because balancing operations (or using self-balancing trees like > splay trees) introduce additional overhead. And - except for > pathological situations where all data are inserted in sequentially > ascending or descending order - this performs surprisingly well.
interesting. > 'balance' does not "re"-balance the tree. Instead, it builds an > optimally balanced tree, only once in the beginning. This is most > useful in situation like we had with this unicode index, which is > not modified thereafter but only used for rapid lookup. So 'idx' is usually used with data that don't change? How does indexing in the database work for example? > BTW, there is also an external program "@bin/balance" which does the > same by reading from a file. It can typically be used as: > > (in (list "bin/balance" "-sort" MyFile) > (while (line) > .. > > (The "-sort" is not needed when the file is already sorted) I saw the proram, but I haven't had a chance to find out what for, when and how to use it yet;-) > If you insert cells or lists with the key in the CAR, you can use > 'lup' to lookup the data. I see, that's what I was thinking about. > the typical key-value situation, symbols work best, though. You can, > for example, convert a numeric key to a symbol with 'format', and Is this generally prefered to using lup? Thank you, Tomas -- UNSUBSCRIBE: mailto:picol...@software-lab.de?subject=unsubscribe
