Dylan Beaudette-2 wrote: > > On Thursday 28 June 2007 06:42, Markus Neteler wrote: >> Dylan Beaudette wrote on 06/26/2007 07:33 PM: >> > Hi, >> > >> > I have found that using the GRASS classification modules work well when >> > the inputs come from discreet (0-255) distributions- for example >> landsat >> > channels, etc. - however I seem to get a lot of singularity problems, >> or >> > maps with a single class when using floating point values of different >> > magnitude. >> >> Dylan, *, >> >> there is i.pr available in the GRASS Addons repository from Stefano >> Merler (my colleague from IRST): >> https://grasssvn.itc.it/grasssvn/grassaddons/trunk/grassaddons/ >> >> " >> * pr : C code for classification problems. It implements k-NN >> (multiclass), classification trees (multiclass), maximum likelihood >> (multiclass), Support Vector Machines (binary), bagging versions of all >> the base classifiers, AdaBoost for binary trees and support vector >> machines. It allows feature manipulation (normalization, principal >> components,...). It also implements feature selection techniques (RFE, >> E-RFE,...), statistical tests on variables, tools for resampling >> (cross-validation and bootstrap) and cost-sensitive techniques for trees >> and support vector machines. Feature selection techniques and >> statistical tests are not distributed in the current release. >> >> ||| * i.pr : a version of pr implemented in the GIS GRASS for dealing >> >> with images. >> >> |" >> >> Maybe interesting? >> Markus >> > > This might be just the ticket. I was hoping to avoid a constant jump back > and > forth between GRASS and R (although it may be worth it...?) -- so the i.pr > routines sound great. Any word on weather or not this module will end up > in > the main distribution of GRASS ? Perhaps I can do some testing and report > back. >
Yes, would be great. After a good testing period it should go into the main distro. Markus -- View this message in context: http://www.nabble.com/grass-classification-routines-and-small---large-numbers-tf3983765.html#a11356553 Sent from the Grass - Dev mailing list archive at Nabble.com. _______________________________________________ grass-dev mailing list [email protected] http://grass.itc.it/mailman/listinfo/grass-dev
