2011/3/23 Francesc Alted <fal...@pytables.org>: > 2011/3/23 brunetto <brunetto.zi...@gmail.com> >> >> For now the leaves max size is 300 (that is: leaves are Arrays >> containing 300 or less integers), the number of nodes dipends on the >> dimension of the dataset. Now I'm using dataset between 1000 and 10^8 >> elements. The tree is built splitting every node (=PyTables Group) in >> two children until the number of elements is <=300. > > I see. May I ask why you use the 300 magic figure? >From a PyTables > performance point of view, perhaps it might make more sense to have larger > Arrays and lesser nodes.
Because my tree comes from a previus in-memory implementation... At that time I did some tests and I found that on average the max speed correspond to leaves of <= 300 elements. I think this is because of what I do when I open a leaf, i.e. calculate distances and sorting arrays. Bigger leaves lead to longer operation on them! Also I can't use the walkNode method because I have a selective travers that automatically exclude all the nodes (and their subnodes) that are more distant than a certain quantity (spatially distant... every node has spatial coordinates). brunetto ------------------------------------------------------------------------------ Enable your software for Intel(R) Active Management Technology to meet the growing manageability and security demands of your customers. Businesses are taking advantage of Intel(R) vPro (TM) technology - will your software be a part of the solution? Download the Intel(R) Manageability Checker today! http://p.sf.net/sfu/intel-dev2devmar _______________________________________________ Pytables-users mailing list Pytables-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/pytables-users
