Chapter 6 -- Page 220 -- Listing 6.9

This listing has transposed the width and height in lines 7 and 8.  The row should iterate over the height and the column over the width.  The correct version is:

   
def double(oldimage):
   oldw = oldimage.getWidth()
   oldh = oldimage.getHeight()

   newim = EmptyImage(oldw*2,oldh*2)

   for row in range(newim.getHeight()):  
       for col in range(newim.getWidth()):
          
           originalCol = col//2 
           originalRow = row//2 
           oldpixel = oldimage.getPixel(originalCol,originalRow)

           newim.setPixel(col,row,oldpixel)

   return newim