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sandefan (39) [Avatar] Offline
#1
Hi,

after a lenghty abstinence from Python I am back again, trying to port "Hello World" samples to python3.

I have a problem with listing 16.7, p. 185, "Drawing art": after running the program I get this error message:

Traceback (most recent call last):
File "chap16_7HelloWorldOrig.py", line 21, in <module>
color_name = random.choice(THECOLORS.keys())
File "/usr/lib/python3.2/random.py", line 252, in choice
return seq"["i"]"
TypeError: 'dict_keys' object does not support indexing


------------------
(program exited with code: 1)
Press return to continue


It is the line
color_name = random.choice(THECOLORS.keys())
that causes the problem.

Would you know how to adapt this line to python3 (version 3.2.3)?

Thank you,

sandefan

P.S. I have a work-around, but is not very elegant smilie
sandefan (39) [Avatar] Offline
#2
Re: Chapt. 16, "Drawing art": 'dict_keys' object does not support indexing!?
I found a solution to the 'dict_keys' problem, but I am too much a newbie to undertand it. Maybe somebody here can help?

In:
http://stackoverflow.com/questions/17322668/xi-xj-xj-xi-typeerror-dict-keys-object-does-not-support-indexing
user user4815162342 writes:

"You're passing the result of somedict.keys() to the function. In Python 3, dict.keys doesn't return a list, but a set-like object that represents a view of the dictionary's keys and (being set-like) doesn't support indexing.
To fix the problem, use list(somedict.keys()) to collect the keys, and work with that"

How am I going to do that with the Hello World example shown in my first post above?

Thank you,

sandefan
sandefan (39) [Avatar] Offline
#3
Re: Chapt. 16, "Drawing art": 'dict_keys' object does not support indexing!?
I found a better solution for listing 16.7 with python3 (though it is still more lengthy than with python2):

...
import pygame, sys, random
from pygame.color import THECOLORS
keys = list(THECOLORS)
...
for i in range (100):
width = random.randint(0, 250)
height = random.randint(0, 100)
top = random.randint(0, 400)
left = random.randint(0, 500)
line_width = random.randint(1, 5)
color_name = random.choice(keys)
color = THECOLORS[color_name]

pygame.draw.rect(screen, color, [left, top, width, height], line_width)
pygame.display.flip()
....


Anybody find something more simple?

Thank you,

sandefan