from java.lang import System
from java.lang import Math
from ij.process import FloatProcessor
from ij import IJ
from ij import ImagePlus

t0 = System.currentTimeMillis()
size = 512
ip = FloatProcessor(size,size)
for y in range(0, size):
   IJ.showProgress(y,size-1)
   for x in range(0, size):
      dx=x-size/2; dy=y-size/2;
      d = Math.sqrt(dx*dx+dy*dy)
      ip.setf(x,y,-d)

time = str((System.currentTimeMillis()-t0)/1000) + " seconds"
img = ImagePlus(time,ip)
IJ.run(img,"Red/Green","")
img.show()