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GNUPLOT

Gnuplot is a program for generating graphs of mathematical functions and numerical data in two and three dimensions. It is usually used in the form of scripts that we can configure in great detail according to the type of data we visualise in our work, obtaining very professional results.

Montseny profile

We draw in a graph the paragliding flight profile from Turó de l'Home, in the Montseny Natural Park (Catalonia), considering two glide ratio lines (7:1 and 8:1), to study at which heights we reach above the landing field. Terrain profile perfil164.txt, 7:1 glide profile gr7-1.txt, 8:1 glide profile gr8-1.txt. The code is pperfil.gnu, and the result:

#!/usr/bin/gnuplot
set title 'Montseny profile bearing 164 SE'
set terminal png
#set size ratio 1
set grid
set nokey
set xlabel "Distance in metres"
set ylabel "Height in metres"
set xrange [0:7500]
set yrange [200:1600]
set ytics 100
set label "Flight 1525 m" at 20,1560 left 
set label "Road" at 940,1130 left
set label 3 "Ciuret stream - Fontmartina" at 1180,1020 left
set label 4 "Road - Can Pla - Can Verdaguer" at 3380,700 left
set label 5 "Line - Campins" at 5470,350 left
set label 6 "Landing 266 m" at 6350,266 left
set label 7 "Glide 7:1" at 1170,1223,0 tc lt 1 rotate by 0
set label 8 "Glide 8:1" at 2000,1300,0 tc lt 3 rotate by 0
set label 9 "727 m" at 6390,742
set label 10 "612 m" at 6390,627
plot 'perfil164.txt' using 1:2 with lines 2, \
     'gr7-1.txt' using 1:2 with lines 1, \
     'gr8-1.txt' using 1:2 with lines 3
set out 'perfil.png'; replot
pause -1

Medusa

Graphical representation of the oscillations observed in the parachute shape of the Russian Soyuz capsule, according to my own mathematical interpretation: gnuSoyuz parachute. Source code: medusa.gnu and the graphic result:

# gnuplot MEDUSA movements
# and writes plot
# Pere Casellas
# v0.1 2016-09-18

# set terminal png
# set output "plot.png"
# unset terminal

set grid

set xrange[0:6]
set yrange[-4:4]
set xlabel "Time (s)"
set ylabel ""
set title "Medusa movements, theoretical analysis"

w= 2.618

plot 0.305*sin(w*x) title "Vertical displacement (m)", \
     0.5*w*cos(w*x) title "0.5 x Vertical speed (m/s)", \
     -0.1*w*w*sin(w*x) title "0.1 x Acceleration (m/s2)", \
     -0.2500*w*w*sin(w*x) title " 0.001 x Additional load (daN)"

# set key left width 1 height 1 box ls 7

  set key left