Generating gnuplot eps files via script in php

I asked a similar question a few days ago, but this is of a slightly different flavor; certainly more specific.

I have开发者_StackOverflow社区 a php file that creates a gnuplot script dynamically, and then runs that script using 4 text files (1 per line of the plot) created beforehand with another php file.

The problem is that the graph.eps files are generated blank and I cannot figure it out. I have a feeling that it has something to do with the directory the text files are in.

This is the file I generate and then run.

set terminal postscript enhanced color
set size ratio 0.7058
set output '/srv/../A.2.5.1a.eps'
set grid

set key font "Arial,10"
set key center bot
set key out vertical
set key horizontal center
set key box

set style line 1  linetype 1 linecolor rgb "red"  linewidth 2.000 pointtype 6 pointsize     default
set style line 3  linetype 1 linecolor rgb "#DAA520"  linewidth 2.000 pointtype 6 pointsize default
set style line 4  linetype 1 linecolor rgb "#006400"  linewidth 2.000 pointtype 6 pointsize default
set style line 6  linetype 1 linecolor rgb "blue"  linewidth 2.000 pointtype 6 pointsize default

set multiplot
set palette model RGB functions 0.8+gray/3, 0.8+gray/3, 0.8+gray/3
set pm3d map
set isosample 100,100

unset colorbox
unset border
unset xtics
unset ytics
set nokey
set nolabel
set size 1.025,1.2
set origin -0.021,-0.06

splot y t ' '

set title "SECTION A.2.5.1a TEST RESULTS"
set key box
set key horizontal center bot
set y2tics 0 , 200
set ytics nomirror
set xtics nomirror

set border
set xtics 250
set xtics font "Arial,8"
set ytics 1750
set size 1,1
set xtics out offset -1,-0.5
set xtics rotate by 45

unset origin
unset x2tics

set xlabel "Loop Length, 26AWG(kft)"
set ylabel "Downstream Data Rate (kbps)"
set y2label "Upstream Data Rate (kbps)"
set xrange [ 250 : 5500 ] noreverse nowriteback
set yrange [ 0 : 14000 ] noreverse nowriteback
set y2range[ 0 : 1400 ] noreverse nowriteback
set bmargin  7

plot    "DSE_A.2.5.1a.txt"  ls 4 title 'Expected Downstream Rate' with linespoints,      \
"DS_A.2.5.1a.txt" ls 1 title 'Measured Downstream Rate' with linespoints, \
\
"USE_A.2.5.1a.txt"  axes x1y2 ls 6 title 'Expected Upstream Rate' with linespoints, \
"US_A.2.5.1a.txt"  axes x1y2 ls 3 title 'Measured Upstream Rate' with linespoints

unset multiplot

Once this is created, I use:

exec( "{$pathName} gnuplot {$File}");

The $pathName is the CWD for the file and the $File variable explains itself.

I've tried using plot $pathname/DS_A.2.5.1a.txt, etc but that doesn't work either.

Thanks for your time and I apologize about the lengthy post. I changed the set output path because it was very long and contains relatively private information.

Thanks and I look forward to all responses!

Edit: I just read http://linux.byexamples.com/archives/487/plot-your-graphs-with-command-line-gnuplot/ and I think that maybe not chmod-ing and that other command might be a problem, but when I try that it still doesn't work.

Since it's being run remotely on a server I do not get the error messages that I do when I manually run gnuplot.

---

It may be instructive to display the executed command. Instead of:

exec( "{$pathName} gnuplot {$File}");

try

$command_to_execute = "$pathName gnuplot $File";
echo $command_to_execute . "\n";
exec( $command_to_execute );

It appears that your path to gnuplot is invalid. You may need to remove the space, like this:

$command_to_execute = "{$pathName}gnuplot {$File}";

and you may need to add a slash, like this:

$command_to_execute = "{$pathName}/gnuplot {$File}";