python getting a list from

Question

thedeck1.txt

1 4 7 10 13 16 19 22 25
5 3 6 9 12 15 18 21 24
27 2 28 8 11 14 17 20 23 26 

thedeck2.txt

1 7
4
10 13 16
19 22 25 28 3
6
9
12 15 18 21 24 27 2 5 8 11 14 17 20 23 26

function.py

 def readingdeck(file):
 file = open(deck1.txt(or also deck2.txt), 'r')
 total_deck = []
 string_counter = 0
 for line in file:
 newline = line.rstrip('\n') 
 for deck_char in newline:
 if (string_counter + 1 < len(newline)):
 if (string_counter == 0) and (newline[string_counter + 1] == ' '):
 total_deck.append(deck_char)
 elif (string_counter == 0) and (newline[string_counter + 1] != ' '):
 total_deck.append(int((str(newline[string_counter])) + str(newline[string_counter + 1]))) 
 elif (string_counter >= 2): 
 if (newline[string_counter] != ' ') and (newline[string_counter + 1] == ' ') and (newline[string_counter - 1] == ' '):
 total_deck.append(deck_char)
 elif (newline[string_counter] != ' ') and (newline[string_counter + 1] != ' '):
 total_deck.append(int((str(newline[string_counter])) + str(newline[string_counter + 1])))
 string_counter += 1
 string_counter = 0
 new_list = [] 
 for item in total_deck:
 if type(item) == str:
 new_list.append(int(item))
 else:
 new_list.append(item)
 return new_list

Hi. So what i want this to do is print

[1, 4, 7, 10, 13, 16, 19, 22, 25, 28, 3, 6, 9, 12, 15, 18, 21, 24, 4, 2, 5, 8, 11, 14, 17, 20, 23, 26]

(ie, all of the number in a list) it does it successfully for thedeck1.txt, but it fails (gives a string out of range error) when i try it for thedeck2.txt.

Any suggestions?

• DSM: That's very low-level. Is there some reason you're working character by character, like an assignment requirement or something?
• Michael C: No, I just want it to add the numbers to a list. No assignment.
• DSM: That's good news-- in that case, you can save yourself a lot of effort, as in @Brionius' answer.

Answer 1

That seems like a pretty complicated method. Here's a simpler way:

def read_deck(filename):
 with open(filename, 'r') as f: # Opens the file and assigns the file object to the name `f` (also makes sure the file will be closed properly)
 contents = f.read().split() # Reads the entire file, then splits it into a list of strings by whitespace (i.e. a space, a newline, whatever)
 return [int(x) for x in contents] # Converts the list of strings to a list of ints

• Michael C: You sir are fabulous. Thank you very much.

Answer 2

Here is an annotated function

import itertools
def read_file(file_name):
 # Open the file
 with open(file_name) as fn:
 # This line makes an iterable that contains each number in your
 # file, but stored as a string.
 # `.split()` separates the numbers by whitespace
 file_contents = [line.split() for line in fn]
 # Turn all the strings into numbers
 # itertools.chain is a way to make this list of lists into a single list
 return [int(num) for num in itertools.chain(*file_contents)]

• Brionius: Just a note: strip isn't necessary, since split with no sep argument ignores leading or trailing whitespace.
• SethMMorton: @Brionius Well, you learn something new every day... Thanks!