NAME

       gbker - Produce kernel density estimation

SYNOPSIS

       gbker [options]

DESCRIPTION

       Compute  the  kernel density estimation on an equispaced grid. Data are read from standard
       input. The kernel bandwidth, if not provided with the  option  -H,  is  set  automatically
       using  simple  heuristics.  Normally  the whole support is displayed. The option -w can be
       used to restrict the computation to specific range of values. The method used  to  compute
       the density is set by the option -M.  The boundaries of the grid are slightly different in
       the different cases.

OPTIONS

       -n     number of equispaced points/bins where the density is computed (default 64)

       -w     set the grid boundaries with min,max (default whole support)

       -H     set the kernel bandwidth

       -S     scale the automatic kernel bandwidth

       -K     choose the kernel to use  (default 0)

       0      Epanenchnikov

       1      Rectangular

       2      Gaussian

       3      Laplacian

       -M     choose the method for density computation (default 0)

       0      use FFT (# grid points rounded to nearest power of 2)

       1      use discrete convolution (compact kernels only; bins>2)

       2      explicit summation (boundaries excluded)

       -F     specify the input fields separators (default " \t")

EXAMPLES

       gbker -n 128 -K 2 < file
              use a Gaussian kernel to compute the density on 128 equispaced points with the  FFT
              approach. All the data in 'file' are used, multiple columns are pooled.

       gbker -K 3 -M 2 < file
              use a Laplacian kernel to compute the density on 64 points.  The method used is the
              explicit summation.

AUTHOR

       Written by Giulio Bottazzi

REPORTING BUGS

       Report bugs to <gbutils@googlegroups.com>

       Package home page <http://cafim.sssup.it/~giulio/software/gbutils/index.html>

COPYRIGHT

       Copyright © 2001-2018 Giulio Bottazzi This program is free software; you can  redistribute
       it  and/or  modify  it  under  the  terms of the GNU General Public License (version 2) as
       published by the Free Software Foundation;

       This program is distributed in the hope that it will be useful, but WITHOUT ANY  WARRANTY;
       without  even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
       See the GNU General Public License for more details.