copy lines from file to list

Question

I need to write a function that read from a file and put every some lines as one cell in a list. I need to copy the lines between 1 to 2 and from 2 to the end and put each of them in different cell in the list, without the lines that contains the number and empty lines. I dont have an idea how make it work.

the file:

; 1

####
# .#
#  ###
#*@  #
#  $ #
#  ###
####

; 2

######
#    #
# #@ #
# $* #
# .* #
#    #
######

my code:

def loader(filename):
    levels=[[]]
    f=open(filename, "r")
    x=[]
    for line in f:
        if ";" not in line:
            x.append(line)
        else:
            levels.append(x)
    f.close()
    return levels

output: cell 1:

####
# .#
#  ###
#*@  #
#  $ #
#  ###
####

cell 2:

######
#    #
# #@ #
# $* #
# .* #
#    #
######

I dont have an expected output to show for example,but I added something to my post — user1816377, Dec 18 '12 at 20:10

jackcogdill · Accepted Answer · 2012-12-18T21:19:53.007

3

Final best solution:

If you use re, you can find anything from

; 1

to

;    2

Here's the code:

import re
levels = [x[2:].strip() for x in re.split(';\s*\d', open(filename).read()) if x != '']

older: (compensates for numbers, and gets rid of blank lines completely)

levels = [x[2:].strip() for x in open(filename).read().split(';') if x != '']

OR

levels = [x[1:].strip() for x in open(filename).read().split('; ') if x.strip() != '']

To print the output:

for level in levels:
    print level

Or individually:

print levels[0]
print levels[1]

edited Dec 18 '12 at 21:19

answered Dec 18 '12 at 20:19

jackcogdill

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but its still copy empty lines, no? and you have any idea how to rid from the numbers? I tried rstrip(int) but there is no such thing – user1816377 Dec 18 '12 at 20:32
If you want to exclude lines with numbers and blank lines, add `if line.strip().strip('\n') != '' and not line.isdigit()` before the `print` statement. – Valdogg21 Dec 18 '12 at 20:41
yes it's! can you explain what the difference pls? can I remove a cell that contain only "" with levels.remove("")? – user1816377 Dec 18 '12 at 21:01
How about now? I didnt quite understand what you were asking though – jackcogdill Dec 18 '12 at 21:03
its worked with the x[2:].forget about what I asked, I got it. but I dont understand what the x[2:] do..can you explain? – user1816377 Dec 18 '12 at 21:06
`x[]` is called `slicing`. It's sort of like a `range`; it only takes the part specified. In `x[2:]` it's taking most of `x`, starting at the 3rd character. Read about it [here](http://docs.python.org/2/library/functions.html#slice). – jackcogdill Dec 18 '12 at 21:09
so its won't help if the number place in the 5th charcter for example – user1816377 Dec 18 '12 at 21:11
And also, on [this post](http://stackoverflow.com/a/509295/1313757) is some very good examples of this. – jackcogdill Dec 18 '12 at 21:12
@user1816377 You're right, it would have to be the 3rd every time. – jackcogdill Dec 18 '12 at 21:12
tnx for your help @yentup!! – user1816377 Dec 18 '12 at 21:13
@user1816377 Wait! I made it so it can find `;` and any number of spaces, and then a number, `1`. Try that code and see if it works. – jackcogdill Dec 18 '12 at 21:20

score 2 · Answer 2 · answered Dec 18 '12 at 20:19

Give this a shot:

def loader(filename):
  levels,x = [],[]
  for line in open(filename,'r'):
    line = line.strip('\n').strip()

    # Skip blank lines
    if line == '':
      continue

    # Assuming that lines containing ';' mark a new cell, so save the old cell
    if ';' in line:
      if x != []:
        levels.append(x)
      x = []

    # If the line doesn't contain ';', it is part of the current cell
    else:
      x.append(line)

  # Save the last cell, if there was one
  if x != []:
    levels.append(x)
  return levels


cells = loader("testfile")

You can build the output for the Nth cell with cell_output = '\n'.join(cell[n-1]):

print '\n'.join(cells[0]) prints your "output cell 1" from above

root · Answer 3 · 2012-12-18T20:54:24.873

2

from itertools import groupby as gb

with open(file,'r') as f:
   [list(g) for k,g in gb(f.readlines(),lambda x:';'in x or x=='\n') if not k]

Out:

[[u'####\n',
  u'# .#\n',
  u'#  ###\n',
  u'#*@  #\n',
  u'#  $ #\n',
  u'#  ###\n',
  u'####\n'],
 [u'######\n',
  u'#    #\n',
  u'# #@ #\n',
  u'# $* #\n',
  u'# .* #\n',
  u'#    #\n',
  u'######\n']]

edited Dec 18 '12 at 20:54

answered Dec 18 '12 at 20:38

root

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copy lines from file to list

3 Answers3