# list index out of range

G

#### Georgy Panterov

I am a relatively new python user. I am writing an economic simulation of a card-game. The simulation runs fine for a few iteration but then it gives an error of "list index out of range."

The strange thing is that it will sometimes run for 10 iterations sometimes for only a few and sometimes won't run at all (seemingly arbitrary).
Here is some of the code:

for _ in range(100):
handA=deal_hand(DECK) #deals 2 'hole' cards from a DECK
handB=deal_hand(DECK)
print handA
print handB
deal_flop(handA,handB,DECK) #appends 3 cards to handA and handB
deal_current(handA,handB,DECK) #appends one more card
deal_rake(handA,handB,DECK) #appends one more card
DECK.extend(list(set(handA+handB))) #returns the cards to the DECK
print winner(handA,handB) #returns 0-draw 1 -playerA win, 2-playerB win

The error message is :

['08C', '10H']
['07S', '03C']
--------
['06C', '02H']
['04D', '12S']
--------
['11H', '14S']
['06S', '04S']
--------

Traceback (most recent call last):
File "G:\Other Stuff\POKER4.py", line 267, in <module>
handB=deal_hand(DECK)
File "G:\Other Stuff\POKER4.py", line 13, in deal_hand
HAND.append(deck)
IndexError: list index out of range

In this case it ran 3 times. It will sometimes run for up to 9-10 times. It seems to be arbitrary but I can't get it to run more than 12 times.

Here is the code for the --deal_***-- functions:

def deal_hand(deck):
HAND=[]
for _ in range(2):
i=random.randint(0,len(deck)) #produces a random card from the deck
HAND.append(deck) # appends the card to the players' hand list
deck.remove(deck) #removes the card from the deck
return HAND

def deal_flop(hand1,hand2,deck):
for _ in range(3):
i=random.randint(0,len(deck))

hand1.append(deck)
hand2.append(deck)
deck.remove(deck)

I would appreciate any help with this
Thanks
George

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I

#### inhahe

random.randint(x,y) returns a random integer between _and including_ x and
y, so randint(0, len(deck)) might return len(deck) and since python's
indices start at 0, the maximum index is len(deck)-1.

rather than using randint(0,len(deck)-1) you could just do
card = random.choice(deck)
HAND.append(card)
deck.remove(card)

although it would be more efficient to do remove card by index which then
gets us back to using randint, like this

i = random.randint(0, len(deck)-1)
HAND.append(deck)
del deck

but i guess speed probably isn't a big factor here

also you could have done
i=random.randint(0, len(deck)-1)
HAND.append(deck.pop(i))

I am a relatively new python user. I am writing an economic simulation of a
card-game. The simulation runs fine for a few iteration but then it gives an
error of "list index out of range."

The strange thing is that it will sometimes run for 10 iterations sometimes
for only a few and sometimes won't run at all (seemingly arbitrary).
Here is some of the code:

for _ in range(100):
handA=deal_hand(DECK) #deals 2 'hole' cards from a DECK
handB=deal_hand(DECK)
print handA
print handB
deal_flop(handA,handB,DECK) #appends 3 cards to handA and handB
deal_current(handA,handB,DECK) #appends one more card
deal_rake(handA,handB,DECK) #appends one more card
DECK.extend(list(set(handA+handB))) #returns the cards to the DECK
print winner(handA,handB) #returns 0-draw 1 -playerA win, 2-playerB win

The error message is :

['08C', '10H']
['07S', '03C']
--------
['06C', '02H']
['04D', '12S']
--------
['11H', '14S']
['06S', '04S']
--------

Traceback (most recent call last):
File "G:\Other Stuff\POKER4.py", line 267, in <module>
handB=deal_hand(DECK)
File "G:\Other Stuff\POKER4.py", line 13, in deal_hand
HAND.append(deck)
IndexError: list index out of range

In this case it ran 3 times. It will sometimes run for up to 9-10 times. It
seems to be arbitrary but I can't get it to run more than 12 times.

Here is the code for the --deal_***-- functions:

def deal_hand(deck):
HAND=[]
for _ in range(2):
i=random.randint(0,len(deck)) #produces a random card from the deck
HAND.append(deck) # appends the card to the players' hand list
deck.remove(deck) #removes the card from the deck
return HAND

def deal_flop(hand1,hand2,deck):
for _ in range(3):
i=random.randint(0,len(deck))

hand1.append(deck)
hand2.append(deck)
deck.remove(deck)

I would appreciate any help with this
Thanks
George

Send instant messages to your online friends http://uk.messenger.yahoo.com

M

#### Mike Kent

def deal_hand(deck):
HAND=[]
for _ in range(2):
i=random.randint(0,len(deck)) #produces a random card from the deck
^ Here i can be from 0 thru (the number of cards in the
deck).
HAND.append(deck) # appends the card to the players' hand list

^ Here you index into the deck to get a
card. The legal indexes are 0 thru (number of cards in the deck - 1)
What happens if i is (the number of cards
in the deck)?
deck.remove(deck) #removes the card from the deck
return HAND