Hmmm. Maybe that line range I gave you was invalid. Basically I meant for you to try removing the code that actually renders the lines (from about where the Draw object is made to where it’s del’ed). That way you could then maybe isolate what’s being done wrong. If you still get an invalid image I’d guess that something isn’t quite right with your install, but as to what…

Have you tried using pil to make a small blank image and save it to file?

No scratch that! Just thing I’ve realised what’s wrong! I’ve been using this on OS X and just opening the file. As you’re on windows you’ll need to open the file in binary mode when you save to it!!

So change:

write_tour_to_img(coords,best,’%s: %f’%(city_file,score),file(out_file_name,’w'))

to:

write_tour_to_img(coords,best,’%s: %f’%(city_file,score),file(out_file_name,’wb’))

(note the extra b)

Hope that helps. Total oversight on my part, but easy enough to fix.

Do I comment those lines in tsp.py? In tsp.py it looks like those lines haves something to do with argument parsing.

The only thing that I could find that was strange was the header of the .png file. When I compared it to http://en.wikipedia.org/wiki/Portable_Network_Graphics#File_header it looks slightly different. I don’t know if that is correct, or if maybe there is something wrong with my system. When I get a chance, I will install Python and PIL on a bare system and see if I get the same problems.

I really want to use this script since it is something that can be easily understood because of the comments and easy readability of python. I just wish that I could find out what was wrong with it! Thanks!

Failing that maybe see if commenting out the code that does the actual drawing (line 156-175) gives you a valid, but empty image.

How big is the image file after the script has run? Maybe it’s just not getting written to disk properly?

However, I ran the program on my windows machine with Python 2.5 and PIL 1.1.6, It ran fine and output what looked to be the correct answer, but, the image is corrupt and I am not able to open it with anything. Did I do something wrong, or is the code possibly not designed for Python 2.5?

I ran this command:
“C:\Python25\python.exe” “C:\part_three\tsp.py” -o “C:\part_three\test.png” -v -n 100000 “C:\part_three\city100.txt” > “C:\part_three\tsp.log”

This was the contents of tsp.log:
100000 -4206.38222041 [11, 49, 74, 43, 38, 8, 14, 79, 20, 82, 87, 60, 69, 77, 44, 66, 92, 5, 68, 0, 35, 39, 56, 73, 86, 9, 30, 50, 99, 31, 19, 96, 10, 21, 34, 88, 67, 22, 18, 36, 16, 61, 41, 63, 23, 1, 90, 97, 78, 26, 54, 84, 3, 51, 48, 65, 47, 71, 53, 15, 32, 94, 55, 76, 95, 72, 58, 37, 45, 6, 93, 12, 2, 25, 98, 40, 91, 17, 29, 89, 27, 70, 33, 24, 46, 81, 7, 57, 59, 28, 85, 83, 80, 4, 42, 75, 62, 64, 13, 52]