Hello group, I've been redicted from usenet ("Convert numpy.ndarray into "normal" array", <75dgm1F16hqntU1@mid.dfncis.de>) here and hope this is the right place. Basically, what I have is a numpy-Array which I got from a FITS-file (it's black/white). I want to display that using GTK. Therefore every color needs to appear three times (to make it look gray R = G = B). The basic framework looks like [...] pb = gtk.gdk.Pixbuf(gtk.gdk.COLORSPACE_RGB, False, 8, width, height) pb_pixels = pb.get_pixels_array() print(type(pb_pixels), pb_pixels.shape, pb_pixels.typecode()) print(type(fits_pixels), fits_pixels.shape, fits_pixels.dtype) which gives (<type 'array'>, (480, 640, 3), 'b') (<type 'numpy.ndarray'>, (480, 640), dtype('uint8')) so now I need to assign values. Naively I started out with for x in range(width): for y in range(height): pb_pixels[y, x] = fits_pixels[y, x] which was horribly slow (around 3 seconds). Thanks to the usenet help, I now got somewhat better: fits_colors = numpy.zeros((height, width, 3), dtype="uint8") for y in range(height): for x in range(width): fits_colors[height - y - 1, x] = fits_pixels[y, x] pb_pixels[:, :] = fits_colors This also works, and is a lot faster (around 0.7 seconds). However, there seems to be a better way to do it. I played around with fits_colors = numpy.fromfunction(lambda y, x, z: fits_pixels[y, x], (height, width, 3), dtype="uint8") pb_pixels[:, :] = fits_colors Which worked somewhat - but gives weird results: The picture is rotatated 90° to the right and the lower left part is displayed repeatedly after 256 pixels... (I can make a screenshot if that's easier). The fromfunction Function is quite fast in my context (around 0.2 second). How should I solve this problem the right way? Kind regards, Johannes