I am trying to plot the datafile but getting this error

Question

~/project$ plot 'dis_xsq_out.dat' u 1:2:3

Command 'plot' not found, but can be installed with:

sudo apt install plotutils

Answer 1

You appear to be trying to run a Gnuplot plot command directly from the terminal shell. Instead, you need to run it from Gnuplot's own interactive shell:

$ gnuplot

    G N U P L O T
    Version 5.2 patchlevel 2    last modified 2017-11-01 

    Copyright (C) 1986-1993, 1998, 2004, 2007-2017
    Thomas Williams, Colin Kelley and many others

    gnuplot home:     http://www.gnuplot.info
    faq, bugs, etc:   type "help FAQ"
    immediate help:   type "help"  (plot window: hit 'h')

Terminal type is now 'wxt'
gnuplot> 
gnuplot> plot 'dis_xsq_out.dat' u 1:2:3

Alternatively, you can run it as a shell one-liner:

gnuplot -p -e 'plot "dis_xsq_out.dat" u 1:2:3'