Dear Riccardo:
As your script works 
with shell switched on with
switch off as default
I simply include int gnuplotversion [4::5]
and instructions and your function
as a public
Oleh
 
25 вересня 2015, 23:10:36, від "Riccardo (Jack) Lucchetti"
<r.lucchetti(a)univpm.it>:
 
   On Fri, 25 Sep 2015, oleg_komashko(a)ukr.net wrote:
 
 > So it would be convenient if gretl
 > have something outputting gnuplot
 > version
 
 Maybe this can help
 
 
 function scalar gnuplot_version(void)
      string tmpfile = "(a)dotdir/gpv.txt"
      !gnuplot --version > @tmpfile
      string s = readfile(tmpfile)
      scalar ret
      sscanf(s, "gnuplot %g", ret)
      return ret
 end function
 
 a = gnuplot_version()
 print a
 
 
 Moreover, debian has a package called "gnuplot5". I don't know if ubuntu 
 users can grab that, or if it's been incorporated into ubuntu already.
 
 
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    Riccardo (Jack) Lucchetti
    Dipartimento di Scienze Economiche e Sociali (DiSES)
 
    Università Politecnica delle Marche
    (formerly known as Università di Ancona)
 
    r.lucchetti(a)univpm.it
    
http://www2.econ.univpm.it/servizi/hpp/lucchetti
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