Re: using gnuplot as a filter

[Ethan M. <merritt@u.washington.edu>]

On Thursday 13 December 2007 05:17, P=C3=A1draig Brady wrote:
> If you write the data to stdin after the plot command, then it works:
> (cat ./plot.gpi; seq 10) | gnuplot > plot.png
>=20
> Ethan's variant here is not as general as it hardcodes the
> source of the data within the script
>=20
> echo 'plot "< seq 10"' | GNUTERM=3Dpng gnuplot > plot.png

You are trying to use gnuplot in a mode it was not designed for.
If it works for you, OK.  But I think that in general this is not
something we should try to support. =20

As I pointed out before, you are assuming that "stdin" is exactly
the same as "current input stream". But it is not the same. =20
Consider the gnuplot commands "load" and "reread", for example.
If either of these is in effect, then  plot '-' will read from
the current command file rather than from stdin. =20

My advice is to write a small perl/python/whatever wrapper to=20
manage the input and output streams.


=2D-=20
Ethan A Merritt