R: [Gdal-dev] trivial (?) optimization for gdal.i:GDALReadRaster( )

[Norman Vine]

Alessandro Amici writes:
> 
> On Thursday 05 February 2004 15:16, Norman Vine wrote:
> > Alessandro Amici wrote:
> > > > if you want to help testing you may try out the attached patch, just
> > > > define the environment variable GDAL_PYTHON_NUMARRAY to anything and
> > > > you get numarray support :).
> >
> > Please note that while Numary is optimized for large vectors it is *much*
> > slower < order of magnitude or so >  with small vectors.  Which may or may
> > not be of consequence depending on your usage.
> 
> well, gdal rasters tend to be 'large vectors' anyhow ;)
>
> BTW, i know numarray had problems in the past, but i read quite some time ago 
> that performance on small arrays was getting better. how recent is your info?

Ahh..  It appears as if Numarray is getting better :-)

from Numarray Homepage
http://www.stsci.edu/resources/software_hardware/numarray

"""numarray is efficient for large arrays (>20,000 elements) 
but is slower than Numeric for small arrays by a factor of 2 to 4. """

Cheers

Norman