clifford-pure-R.R

a=-1.24458046630025
b=-1.25191834103316 
c=-1.81590817030519 
d=-1.90866735205054

n <- 10000000
x <- vector("numeric", n)
y <- vector("numeric", n)
x[1] <- 0
y[1] <- 0

t1 <- proc.time()
for(i in 2:n) {
  x[i] <- sin(a * y[i-1] + c * cos(a * x[i-1]))
  y[i] <- sin(b * x[i-1] + d * cos(b * y[i-1]))
}
df <- data.frame(x = x, y = y)
proc.time() - t1

#   user  system elapsed 
#  4.483   0.065   4.876 

Hi, harnagpal.
Currently I'm developing a tool to produce those a, b, c, d values automatically.

I found this gist looking for a more efficient way of drawing them.
It is a WIP, it has not a very good UI so far, but you can use it: https://davidomarf.github.io/attractor-seeder/

Just click on the "Generate" button. To generate new values, press space bar one time.
To avoid a certain attractor from being re-drawn, click the lock button that appears when you hover the attractor.
To copy the a, b, c, d values, click the clipboard icon.
To draw the attractor in a higher-quality image, click the "external link" icon.