Francesc Alted <faltet <at> pytables.org> writes: > A Wednesday 23 June 2010 22:17:23 Felix Schlesinger escrigué: > > I am dealing with a large table. One of the columns of that table should > > hold a variable number of pairs of integers. In order to implement this I > > use a pytables table for the fixed columns and a seperate VLArray of > > IntAtom(4,2) for the variable column. > > Which is the approximate number of entries on each row?
Between 1 and 5. > What about using an CArray for all the IntAtom(4,2) atoms, named say, > 'values' > and an additional array (saved in a different CArray or even in an > attribute), > say 'indices', for keeping track of the different 'row' indices. I am doing something like this. Many rows in the VLArray would have length 0. I am not creating those rows and instead putting the index of the relevant VLArray row into each table row (or -1 if there is no VLArray row). I could use an EArray and put start:stop into the table. Are appends to an EArray faster then to a VLArray? But since I do not know the size in advance, I need some data structure to collect all the items before I can create a CArray. I can benchmark it with numpy.append or with simple lists. Thanks Felix ------------------------------------------------------------------------------ ThinkGeek and WIRED's GeekDad team up for the Ultimate GeekDad Father's Day Giveaway. ONE MASSIVE PRIZE to the lucky parental unit. See the prize list and enter to win: http://p.sf.net/sfu/thinkgeek-promo _______________________________________________ Pytables-users mailing list Pytables-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/pytables-users
