from Lorenz attractor plotting example:
require "numo/gnuplot"
def lorenz(x, y, z, s: 10, r: 28, b: 2.667)
x_dot = s * (y - x)
y_dot = r * x - y - x * z
z_dot = x * y - b * z
[x_dot, y_dot, z_dot]
end
dt = 0.01
stepCnt = 10_000
xs, ys, zs = [0.0], [1.0], [1.05]
stepCnt.times do |i|
# Derivatives of the X, Y, Z state
x_dot, y_dot, z_dot = lorenz(xs[i], ys[i], zs[i])
xs[i + 1] = xs[i] + (x_dot * dt)
ys[i + 1] = ys[i] + (y_dot * dt)
zs[i + 1] = zs[i] + (z_dot * dt)
end
Numo.gnuplot do
set term: "pngcairo", size:[600,600]
set output: "lorenz.png"
set xlabel: "X Axis"
set ylabel: "Y Axis"
set zlabel: "Z Axis"
set title: "Lorenz Attractor"
set grid: "xtics ytics ztics"
set xyplane_at: 0
unset :key
set view: [60,30,1,1]
splot xs, ys, zs, w:"lines", lw:0.5, lc_rgb:"blue"
set term: "gif", animate:true, delay:50, size:[600,600]
set output: "lorenz.gif"
12.times do |i|
set view: [80-i*5,10+i*15,1,1]
splot xs, ys, zs, w:"lines", lw:1, lc_rgb:"blue"
end
end
