Animated heart using R

February 8th, 2016 | Categories: programming, python, R, walking randomly | Tags:

While waiting for the rain to stop before heading home, I started messing around with the heart equation described in an old WalkingRandomly post. Playing code golf with myself, I worked to get the code tweetable. In Python:

from pylab import *
x=r_[-2:2:0.001]
show(plot((sqrt(cos(x))*cos(200*x)+sqrt(abs(x))-0.7)*(4-x*x)**0.01)) pic.twitter.com/gbOTbYSaIG

— Mike Croucher (@walkingrandomly) February 8, 2016

In R:

x=seq(-2,2,0.001)
y=Re((sqrt(cos(x))*cos(200*x)+sqrt(abs(x))-0.7)*(4-x*x)^0.01)
plot(x,y)#rstats pic.twitter.com/trpgEnNna4

— Mike Croucher (@walkingrandomly) February 8, 2016

I liked the look of the default plot in R so animated it by turning 200 into a parameter that ranged from 1 to 200. The result was this animation:

Finding this animation based on previous tweets oddly mesmerising #rstats pic.twitter.com/e3q6lZqWcP

— Mike Croucher (@walkingrandomly) February 8, 2016

The code for the above isn’t quite tweetable:

options(warn=-1)
for(num in seq(1,200,1))
{
    filename = paste("rplot" ,sprintf("%03d", num),'.jpg',sep='')
    jpeg(filename)
    x=seq(-2,2,0.001)
    y=Re((sqrt(cos(x))*cos(num*x)+sqrt(abs(x))-0.7)*(4-x*x)^0.01)
    plot(x,y,axes=FALSE,ann=FALSE)
    dev.off()
}

This produces a lot of .jpg files which I turned into the animated gif with ImageMagick:

convert -delay 12 -layers OptimizeTransparency -colors 8 -loop 0 *.jpg animated.gif

Walking Randomly