bionic (1) pkfssvm.1.gz

Provided by: pktools_2.6.7.3+ds-1_amd64 bug

NAME

       pkfssvm - feature selection for nn classifier

SYNOPSIS

       pkfssvm -t training -n number [options] [advanced options]

DESCRIPTION

       Classification  problems  dealing  with  high dimensional input data can be challenging due to the Hughes
       phenomenon.  Hyperspectral data, for instance, can have hundreds of spectral bands  and  require  special
       attention  when  being  classified.   In  particular  when  limited  training  data  are  available,  the
       classification of such data can be problematic without reducing the dimension.

       The SVM classifier has been shown to be more robust to this type of problem than  others.   Nevertheless,
       classification  accuracy  can  often  be  improved  with  feature selection methods.  The utility pkfssvm
       implements a number of feature selection techniques, among which a  sequential  floating  forward  search
       (SFFS).

OPTIONS

       -t filename, --training filename
              training  vector  file.   A single vector file contains all training features (must be set as: B0,
              B1, B2,...) for all classes (class numbers identified by label  option).   Use  multiple  training
              files  for  bootstrap aggregation (alternative to the bag and bsize options, where a random subset
              is taken from a single training file)

       -n number, --nf number
              number of features to select (0 to select optimal number, see also --ecost option)

       -i filename, --input filename
              input test set (leave empty to perform a cross validation based on training only)

       -v level, --verbose level
              set to: 0 (results only), 1 (confusion matrix), 2 (debug)

       Advanced options

       -tln layer, --tln layer
              training layer name(s)

       -label attribute, --label attribute
              identifier for class label in training vector file.  (default: label)

       -bal size, --balance size
              balance the input data to this number of samples for each class (default: 0)

       -random, --random
              in case of balance, randomize input data

       -min number, --min number
              if number of training pixels is less then min, do not take this class into account

       -b band, --band band
              band index (starting from 0, either use band option or use start to end)

       -sband band, --startband band
              start band sequence number

       -eband band, --endband band
              end band sequence number

       -offset value, --offset value
              offset value for each spectral band input features: refl[band]=(DN[band]-offset[band])/scale[band]

       -scale value, --scale value
              scale value for each spectral band input features: refl=(DN[band]-offset[band])/scale[band] (use 0
              if scale min and max in each band to -1.0 and 1.0)

       -svmt type, --svmtype type
              type of SVM (C_SVC, nu_SVC,one_class, epsilon_SVR, nu_SVR)

       -kt type, --kerneltype type
              type of kernel function (linear,polynomial,radial,sigmoid)

       -kd value, --kd value
              degree in kernel function

       -g value, --gamma value
              gamma in kernel function

       -c0 value, --coef0 value
              coef0 in kernel function

       -cc value, --ccost value
              the parameter C of C-SVC, epsilon-SVR, and nu-SVR

       -nu value, --nu value
              the parameter nu of nu-SVC, one-class SVM, and nu-SVR

       -eloss value, --eloss value
              the epsilon in loss function of epsilon-SVR

       -cache number, --cache number
              cache memory size in MB (default: 100)

       -etol value, --etol value
              the tolerance of termination criterion (default: 0.001)

       -shrink, --shrink
              whether to use the shrinking heuristics

       -sm method, --sm method
              feature  selection method (sffs=sequential floating forward search, sfs=sequential forward search,
              sbs, sequential backward search, bfs=brute force search)

       -ecost value, --ecost value
              epsilon for stopping criterion in cost function to determine optimal number of features

       -cv value, --cv value
              n-fold cross validation mode (default: 0)

       -c name, --class name
              list of class names.

       -r value, --reclass value
              list of class values (use same order as in --class option).

SEE ALSO

       pkfsann(1)

                                                07 February 2018                                      pkfssvm(1)