Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail
From: John Edwards <johned0@gmail.com>
Newsgroups: comp.graphics.apps.gnuplot
Subject: Re: problem piping commands to gnuplot under Windows
Date: Sun, 12 Jan 2014 08:17:20 +0000
Lines: 62
Message-ID: <bjf1ciFd0kqU1@mid.individual.net>
References: <bje5c6F7tvaU1@mid.individual.net>
Reply-To: johned0@gmail.com
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
X-Trace: individual.net 0UATN74WFfxLDCTOTDm9uwAdhcI5kNElcAUNPAR9CGMwPKMi7C
Cancel-Lock: sha1:+nBOsKJQEKvRdzbL7v7V3+aFeiw=
User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0
In-Reply-To: <bje5c6F7tvaU1@mid.individual.net>
Xref: csiph.com comp.graphics.apps.gnuplot:2253

I had a bit of a lightbulb moment while waking up this morning and 
wondered if it was a CR/LF problem and sure enough the following code 
works fine :

fprintf (gnuplotPipe, "plot \"1.tmp\" using 1:2 title \"Data set 0\" 
with lines lc rgb \"purple\", \\\r");

Note the \r rather than \n.
Does anyone think this should be reported as a bug ?
Cheers,
John


On 12/01/2014 00:19, John Edwards wrote:
> Hello again folks,
>
> I am trying to plot two data files using the following code :
>
> #include <stdlib.h>
> #include <stdio.h>
>
> void main()
> {
>    FILE * gnuplotPipe = _popen ("gnuplot -persist", "w");
>    FILE * f1 = fopen("1.tmp", "w");
>    FILE * f2 = fopen("2.tmp", "w");
>    int i;
>
>    for (i = 0; i < 5; i++)
>    {
>      fprintf (f1, "%lf %lf\n", (float)i, (float)i);
>      fprintf (f2, "%lf %lf\n", (float)i, (float)i+1);
>    }
>    fclose (f1); fclose (f2);
>
>    fprintf (gnuplotPipe, "plot \"1.tmp\" using 1:2 title \"Data set 0\"
> with lines lc rgb \"purple\", \\\n");
>    fprintf (gnuplotPipe, " \"2.tmp\" using 1:2 title \"Data set 1\" with
> lines lc rgb \"green\"\n");
>    fflush (gnuplotPipe);
>    getchar ();
>    fprintf (gnuplotPipe, "exit\n");
>    _pclose (gnuplotPipe);
> }
>
> This works fine if I run the plot command in gnuplot from a script or if
> I use pgnuplot but when I use gnuplot I get the following error message :
>
> gnuplot> plot "1.tmp" using 1:2 title "Data set 0" with lines lc rgb
> "purple", \
>  >
> gnuplot>  '2.tmp' using 1:2 title "Data set 1" with lines lc rgb "green"
>           ^
>           invalid command
>
> Can anyone tell me if I am being a numpty ?
>
> Thanks very much,
> John
>
>