Problem with atribuition in lists

[lumeniel]

Hi

I have this code and a problem that i don't understand. In image_matrix, a PixelArray object where there is a image. I want to separate this image in frames then I capture pixel by pixel in a double for with the dimensions of frame. The variable h represents each image. self.TileSnc is a list. Each position of this list represent an image that I read and contains another list with each frame of image. The problem is:
Every time that the for h in range(int(max_pos)) executes the line self.TileSnc[stat][pos] = image_sonic would be put the frame (image_sonic) in the position pos, but every positions in self.TileSnc[stat] received the same frame. Can someone say me what's wrong with my code. Thank you very much.

for h in range(int(max_pos)):
	        pos = pos + 1
                for i in range(int(height)):
	            for j in range(int(frame)):
	                image_sonic[j][i] = image_matrix[frame*(pos-1)+j][i]

		self.TileSnc[stat][pos] = image_sonic

[Gribouillis]

I think the problem is that you always use the same image_sonic . For example, each time you go through the double for i ... for j ... , the value of image_sonic[0][0] is modified, but since all self.TileSnc[stat][pos] are this same image_sonic object (or array), evrey loop erases the previous one.
What you should do is to define a new image_sonic object at each loop like this

for h in ...:
  image_sonic = create_frame(int(height), int(frame))
  ...
  for i ...
    for j ...

And create frame is a function returning a new object, like this one if your objects are just arrays

def create_frame(height, width):
  L = []
  for i in range(height):
    L.append([None] * width)
  return L

But may be your array are Numerical python arrays or something else, so write your own create_frame :)

[lumeniel]

You really help me.

Thank you so much