[R] Animated lissajous

From: <rlist.10.phftt_at_xoxy.net>
Date: Sun 16 Oct 2005 - 13:34:29 EST


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



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https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html Received on Sun Oct 16 13:42:28 2005

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