It is converted to Fortran order for efficiency reasons. The most repeated and consuming operation is the search for split thresholds, which is performed column-wise, hence the Fortran ordering.
Gilles On 10 January 2012 09:39, Andreas <[email protected]> wrote: > Hey everybody. > Looking a bit into my memory problems, the first thing I noticed > is that the "fit" method of BaseDecisionTree converts > the data into float32 and Fortran-Style ordering. > I haven't paid much attention to that but is that a common pattern? > Having float32 seems reasonable and this conversion is also > done in the SVMs. But there it is also mentioned explicitly in the docs. > > Converting the input to Fortran-style ordering seems a bit weird to > me, as I thought the convention was that the data is assumed > to be C-ordered. > Is there an efficiency reason for doing this that can not be > circumvented? > > Another thing I don't like so much is that the conversion > into float32 is not very explicit, since a type is defined > in the _tree.pyx, then imported into tree.py and used > for conversion there. > I no-one disagrees I would very much prefer to make > the type explicit in tree.py. > > Any hints on the Fortran style ordering would be very welcome. > > Thanks, > Andy > > ------------------------------------------------------------------------------ > Write once. Port to many. > Get the SDK and tools to simplify cross-platform app development. Create > new or port existing apps to sell to consumers worldwide. Explore the > Intel AppUpSM program developer opportunity. appdeveloper.intel.com/join > http://p.sf.net/sfu/intel-appdev > _______________________________________________ > Scikit-learn-general mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/scikit-learn-general ------------------------------------------------------------------------------ Write once. Port to many. Get the SDK and tools to simplify cross-platform app development. Create new or port existing apps to sell to consumers worldwide. Explore the Intel AppUpSM program developer opportunity. appdeveloper.intel.com/join http://p.sf.net/sfu/intel-appdev _______________________________________________ Scikit-learn-general mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/scikit-learn-general
