CODEWITHSUNDEEP
pythonlistsplitappendtuples
exclamationmark1
exclamationmark1

Reputation: 17

.split() and .append information from .txt file as tuples to a new list

I'm trying to read a .txt file line by line with a while loop, split each line at a comma intersection, call a function to return the "date" side of each line to a list, then append the "task" side to the datetime in the list.

Example line in the .txt file: "tutorial signons,28/02/2014"

The result should look like: (datetime.datetime(2014, 2, 28, 0, 0), 'tutorial signons')

My code at the moment is returning this: ['t', 'u', 't', 'o', 'r', 'i', 'a', 'l', ' ', 's', 'i', 'g', 'n', 'o', 'n', 's', ',', '2', '8', '/', '0', '2', '/', '2', '0', '1', '4', '\n']

Datetime Function:

def as_datetime(date_string):
    try:
        return datetime.datetime.strptime(date_string, DATE_FORMAT)
    except ValueError:
        # The date string was invalid
        return None

load_list function:

def load_list(filename):
    new_list = []
    f = open("todo.txt", 'rU')
    while 1:
        line = f.readline()
        line.split(',')
        task = line[1:0]
        datetime = as_datetime(line)
        if not line:
            break
        for datetime in line:
            new_list.append(datetime)
        for task in line:
            new_list.append(task)
        return new_list

Upvotes: 1

Views: 483

Answers (2)

Pi Marillion
Pi Marillion

Reputation: 4674

Just a couple things:

  • Since your date is always on the right, and you may want commas in the command part, consider using rsplit instead of split. Using rsplit(',', 1) will only split at the last comma.
  • Capture the split output to two new variables.
  • Looks like "todo.txt" should be filename the way the function is written.
  • Use with for files where appropriate.
  • I'm not sure the purpose of some of the lower logic. I've written the code below to skip lines with no date or unreadabe date.

The edited version looks like:

DATE_FORMAT = '%d/%m/%Y'
import datetime
def load_list(filename):
    new_list = []
    with open(filename, 'rU') as f:
        for line in f:
            task, date = line.rsplit(',', 1)
            try:
                # strip removes any extra white space / newlines
                date = datetime.datetime.strptime(date.strip(), DATE_FORMAT)
            except ValueError:
                continue # go to next line
            new_list.append((date, task))
    return new_list

This returns a list of tuples. Which you could easily iterate through:

for date, task in load_list('todo.txt'):
    print 'On ' + date.strftime(DATE_FORMAT) + ', do task: ' + task

Finally, I would normally suggest using the csv module, since your file looks like a csv file. If task will never have commas in it, then the csv.reader() functionality can replace rsplit.

Upvotes: 0

jollarvia
jollarvia

Reputation: 379

you have to capture line.split(',') in a variable. split doesn't alter the original variable.

Upvotes: 1

Related Questions