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animationlabelgnuplotparticles

Display a column value in label with gnuplot

I have a program that generates a file with the positions of particles in a box, and data contains also the pressure inside the box (every second let's say). With gnuplot I animate the particles in a loop but I want to display the pressure in a label. Is it possible ?

enter image description here

Here's the file. Pressure is in 4th column

enter image description here

My code :

# Titre du graphique
set title "Mouvement de particules d'Hélium (R = 3e-2 {/Helvetica=10 \305) \n sur une surface de      4 {/Helvetica=10 \305^{2}}"
set xlabel "L {/Helvetica=10 (\305)}"
set ylabel "L {/Helvetica=10 (\305)}"
set style line 2 lc rgb 'blue' pt 7 # cercle
set style fill solid 0.4
unset key
set size square
infile = 'particules.dat'
#stats infile using 1:2 name 'data' nooutput
k=21
do for [i=0:k] {
labels(x,y) = stringcolumn(3)
stats [*:*] infile using 5 name 'pression' nooutput
set label 1 sprintf("Pression : ", pression) at screen 0.2,0.9
plot infile index i using 1:2 with circles ls 2
pause 1.0
}
Solution

  • Not so elegant, but you can use multiplot. Using this as the core of your loop:

    set multiplot

set size 1,1
set origin 0,0

set border
set xtics; set ytics

set xlabel "L {/Helvetica=10 (\305)}"
set ylabel "L {/Helvetica=10 (\305)}"
set title "Mouvement de particules d'Hélium (R = 3e-2 {/Helvetica=10 \305) \n sur une surface de      4 {/Helvetica=10 \305^{2}}"

plot infile index i using 1:2 with circles ls 2

set border 0
unset xtics; unset ytics
unset xlabel; unset ylabel
unset title

set origin -0.35,0.395
plot infile index i u (0):(0):4 w labels

unset multiplot

    MWE

    You may have to play with the current origin values.