Provided by: gbutils_5.7.0-1_amd64

**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-wcan 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**

-nnumber of equispaced points/bins where the density is computed (default 64)-wset the grid boundaries with min,max (default whole support)-Hset the kernel bandwidth-Sscale the automatic kernel bandwidth-Kchoose the kernel to use (default 0) 0 Epanenchnikov 1 Rectangular 2 Gaussian 3 Laplacian-Mchoose 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)-Fspecify 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 © 2001-2015 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.