[beyonder]

Hi everyone,

i have a 3d wind field, in other words a 3d matrix 300*100*200 (using matlab)
i have been making nice videos with curl/isosurface commands ...
lately it has come to my attention that it is possible to use other vortex detection methods such as;
delta criterion,q criterion , lambda 2, curl (most common) at the moment among these I am using the curl of velocity (vorticity) and the q criterion
but i have no idea how you would implement delta criterion or lambda 2#
i know this is a very specific question
but maybe someone could help ?
thanks in advance
there is also a related article but i dont get it http://jeb.biologists.org/content/211/8/1221.long