Thursday, January 19, 2012

Taking a Random Walk with Processing 1.5

If you've ever dabbled with simulations you have probably come across Processing, the open source environment for animation, interaction, and much more.  The Java-ish scripting language allows for quick prototyping and the library of examples allow even beginners (me) to get moving quickly.

To the right is an image I created from a very simple simulation of a "random walk" along the y-axis as time moved along the x-axis.  Many have noted the similarity between this process and the peaks and valleys of markets, mountain ranges, and other stochastic processes.  If you haven't already, give it a try.

Source for Random Walk:
int x, y, r, middle, randOffset, previousX, previousY;

 void setup() {
   size(900, 900);
   background(192, 64, 0);
   x = 0;
   r = 2;
   y = 200;

 void draw() {
   previousX = x;
   previousY = y;
   // y does random up or down of 10 units
   randOffset = 10 - (int)random(21);
   y = y + randOffset;
   //line(150, 25, mouseX, mouseY);
   line(previousX, previousY, x, y);
   if(x < 800) save("random_walk.tif");