One thing that I need is to access columns of my matrix with the same efficiency as I would access them using rows, e.g.
for col in tetrahedrons: # get indices of one element For the moment I implement the above like: for i in range(NCELL): col = tetrahedrons[:,i] # get the element vertices in a fortran/matlab matrix I used to assume this to be efficient as the data in file is oriented column-wise, but am no longer sure, maybe you can clarify. Best regards, Dominik On Mon, Dec 13, 2010 at 10:59 AM, Francesc Alted <fal...@pytables.org>wrote: > A Monday 13 December 2010 10:44:59 Dominik Szczerba escrigué: > > Hi Francesc, > > > > Hearing that row-major order is hardcoded behind the scene is rather > > a bad news for me. > > Mind that the data ordering affects mainly the iterators and the out-of- > core computing machinery (the `tables.Expr` module). Are you going to > use these features in your code? > > > You are right, there is no way to store ordering > > metadata in HDF5, but I do not see any need for any. I have been > > using HDF5 with fortran/matlab data for a very long time. One just > > needs to know the ordering of the data, and/or store it in XDMF > > light xml description. Does this sound reasonable for pytables? > > I think it should be much easier than that: just add a new attribute > called DATA_ORDER (or similar). > > But, provided that you really want to use PyTables machinery that > depends on data-order (iterators and `tables.Expr`), using the > extendable dimensions would not be enough? > > -- > Francesc Alted > > > ------------------------------------------------------------------------------ > Oracle to DB2 Conversion Guide: Learn learn about native support for > PL/SQL, > new data types, scalar functions, improved concurrency, built-in packages, > OCI, SQL*Plus, data movement tools, best practices and more. > http://p.sf.net/sfu/oracle-sfdev2dev > _______________________________________________ > Pytables-users mailing list > Pytables-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/pytables-users > >
------------------------------------------------------------------------------ Oracle to DB2 Conversion Guide: Learn learn about native support for PL/SQL, new data types, scalar functions, improved concurrency, built-in packages, OCI, SQL*Plus, data movement tools, best practices and more. http://p.sf.net/sfu/oracle-sfdev2dev
_______________________________________________ Pytables-users mailing list Pytables-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/pytables-users
