ensure that gnuplot output is directed to the png

Author: berndflemisch

benchmarks/rotating-cylinders/openfoam/plot

@@ -1,4 +1,5 @@
 #!/bin/sh
+cd "${0%/*}" || exit                                # Run from this directory
 # Require gnuplot
 command -v gnuplot >/dev/null || {
     echo "FOAM FATAL ERROR: gnuplot not found - skipping graph creation" 1>&2
@@ -8,6 +9,7 @@ command -v gnuplot >/dev/null || {
 
 gnuplot<<EOF
     set terminal pngcairo font "helvetica,16" size 800,600
+    set output "p.png"
     set xlabel "Radius, r"
     set xrange [1:2]
     set grid
@@ -29,7 +31,6 @@ gnuplot<<EOF
     samples="postProcessing/sample1/1000/centreLine_p_U.xy"
 
     set ylabel "Pressure, p"
-    set output "p.png"
     set samples 20
     set key bottom right
     plot samples u 1:2 w lines lw 2 lc "black" t "OpenFOAM", \
@@ -41,4 +42,5 @@ gnuplot<<EOF
     set key top right
     plot samples u 1:4 w lines lw 2 lc "black" t "OpenFOAM", \
         analytical_utheta(x) w p ps 2 pt 6 lw 2 lc rgb "red" t "analytical"
+    set output
 EOF