从.txt提取数据

Question

i'm doing a sudoku in python and i have a little problem to know how i am supposed to get data from a file

so i have a file with who looks like this :

.3. ... ...
..8 39. 6.. 
5.1 2.. 49.
.7. 6.. ...
2.. ... .4.
... 5.3 98.
... ... 15.
... ..7 ..9
4.. .1. 3..

every nine points it's a "\\n"

How can i get the data?

At the moment, i have just did that:

import os

f = open('sudo.txt', 'r')
lines = f.read()
f.close()

sudoku = lines

print(sudoku)
os.system("pause")

Thanks for your help.

Answer 1

This is actually much more difficult of a question than the other answers seem to be considering. Especially solving the sudoku (which is outside the scope of this question)

Consider what sort of a data structure you want. I'd imagine you'd want to repurpose a list in a custom class

class Puzzle(list):
    pass

and then pass it a list of each number left to right top to bottom, maybe using zero ( 0 ) as the blank space, meaning your constructor should be

Puzzle([0,3,0,0,0,0,0,0,0,0,0,8,3,9,0,6,0,0, ... ])

How would you read this from your target data? Well, one spot at a time.

with open("filename.txt") as inf:
    puzzle = [
        [0 if el == '.' else int(el) for el in line if el.strip()] 
        for line in inf]

That list comp is a bit of a mouthful though. Let's go through it.

puzzle = [ ... ]

Basic list comp syntax. Nothing to talk about here

[ [ 0 if el == '.' else int(el) for el in line if el.strip() ] ... ]

This is the mouthful, but it's basically just a NESTED list comp. This one says

[ 0 if el == '.'
# if the character is a period (.), use a zero (0)
else int(el)
# otherwise, cast the character to integer since it's a number
for el in line
# we're iterating over each character in the string line
if el.strip()
# and selecting every "truthy" character (e.g. skipping the spaces)

The rest of it is simple

[ ... for line in inf]
# "line" is each literal line in the file.

Answer 2

Python loop constructs can basically iterate over anything, including strings, so for something like this, all you have to do is split the string on the newlines to separate the rows, and then iterate through those rows and put them into the array, if they aren't one of the spaces separating the boxes. So assuming you want the board in a 2d array, this list comprehension will do what you ask.

sudoku = [[character for character in line if not character==" "] for line in lines.split("\n")]

Answer 3

readlines will split the data on lines. Also, always use the with statement when opening files.

with open('sudo.txt') as f:
    lines = f.readlines()

You could then parse it further with split:

soduku = [[list(group) for group in line.split()] for line in lines]

Which would put your data in this format:

[[['.', '3', '.'], ['.', '.', '.'], ['.', '.', '.']],
 [['.', '.', '8'], ['3', '9', '.'], ['6', '.', '.']],
 [['5', '.', '1'], ['2', '.', '.'], ['4', '9', '.']],
 [['.', '7', '.'], ['6', '.', '.'], ['.', '.', '.']],
 [['2', '.', '.'], ['.', '.', '.'], ['.', '4', '.']],
 [['.', '.', '.'], ['5', '.', '3'], ['9', '8', '.']],
 [['.', '.', '.'], ['.', '.', '.'], ['1', '5', '.']],
 [['.', '.', '.'], ['.', '.', '7'], ['.', '.', '9']],
 [['4', '.', '.'], ['.', '1', '.'], ['3', '.', '.']]]