[R] Animated lissajous

[Tuszynski, Jaroslaw W.]

Pretty neat. 

Jarek 
====================================================\==== 
 Jarek Tuszynski, PhD.                           o / \ 
 Science Applications International Corporation  <\__,|  
 (703) 676-4192                                   ">  \ 
 Jaroslaw.W.Tuszynski at saic.com                     `   \ 



-----Original Message-----
From: r-help-bounces at stat.math.ethz.ch
[mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of
rlist.10.phftt at xoxy.net
Sent: Saturday, October 15, 2005 11:34 PM
To: r-help at stat.math.ethz.ch
Subject: [R] Animated lissajous

Here's some code to make lissajous dance.  I've attached a small sample GIF.

Cheers,
Rob Steele
robsteele at yahoo dot com



plot.lissajous = function(omega.x, omega.y, delta = 0, num.thetas = 200) {
   thetas = seq(0, 2 * pi, length = num.thetas)
   xs = sin(omega.x * thetas + delta)
   ys = cos(omega.y * thetas)
   plot(xs, ys, type = 'l', lwd = 3, ann = FALSE, axes = FALSE) }


## Show one.
par(mar = c(2, 2, 2, 2))
plot.lissajous(4, 3)

## Animate it.
while (TRUE) {
   for (delta in seq(0, 2 * pi, length = 120)) {
       plot.lissajous(4, 3, delta)
       Sys.sleep(1 / 30)
   }
}


## Show a bunch.
par(mar = c(1, 1, 1, 1))
par(mfrow = c(length(omega.xs), length(omega.ys))) for (omega.x in 1:5) {
   for (omega.y in 1:5) {
       plot.lissajous(omega.x, omega.y, deltas[i])
   }
}

## Animate them.  (Requires ImageMagick.) num.frames = 120 image.dir =
'images'

if (! file.exists(image.dir)) {
   dir.create(image.dir)
}

deltas = seq(0, 2 * pi, length = num.frames)

for (i in 1 : length(deltas)) {
   png(file = file.path(image.dir, sprintf('img-%03d.png', i)))
   par(mar = c(1, 1, 1, 1))
   par(mfrow = c(length(omega.xs), length(omega.ys)))
   for (omega.x in 1:5) {
       for (omega.y in 1:5) {
           plot.lissajous(omega.x, omega.y, deltas[i])
       }
   }
   dev.off()
}

## This ImageMagick command combines the image files into a GIF animation:
# convert -delay 3 images/*.png images/animation.gif