Calculate the average value in each slice

AverageSliceValue.py

image = WindowManager.getCurrentImage()
stack = image.getStack() # get the stack within the ImagePlus
n_slices = stack.getSize() # get the number of slices
# iterate over every slice
for sliceIndex in range(1,n_slices+1):
  curSlice=stack.getProcessor(sliceIndex)
  sumVal=0;countPixel=0
  # iterate over every pixel in the slice
  for cPixel in curSlice.toFloatArrays()[0]: 
    sumVal+=cPixel
    countPixel+=1
  IJ.log("Slice:"+str(sliceIndex)+", Mean:"+str(sumVal/countPixel))