yihui/animation — pull request #38 by yulijia (2013-08-22 04:31:33+00:00)
Title: quincunx2.R

I follow the Keith O’Rourke's code and implement the **quincunx2** function.

Both Keith and I have found in your **qunicunx** function, the matrix **directx** is not 'useful', though I know it contain sthe direction of falling balls. I keep it and also make a matirx **newdirectx** to contain the direction of falling balls in the bottom layers.