making histograms via gnuplot using simple script

making histograms via gnuplot using simple script.

   gnuplot> call “hist_plot” “input_file” “N_col” “width”


---- hist_plot -----------
# this is a script in order to plot a histogram for
# "$1"-th column of the input file "$0" with box-width "$2"
# written by KARISOMEBITO
bin(x,w) = w*floor(x/w) + (w/2.0)
pl "$0" us (bin($$$1,$2)):(1.0) s f w boxes
----------------------------