[Tutor] Retrieving information from a plain text file (WinXP/py2.6.2/Beginner)

[Dave Angel]

(Looks like maybe you hijacked another thread, instead of just creating 
a new message, with new topic, for the list)

Katt wrote:
> <div class="moz-text-flowed" style="font-family: -moz-fixed">Hello all,
>
> Thank you all for your help.  I appreciate it alot.
>
> I have been trying to work with file IO alot recently and would like 
> to improve my little program so that I no longer use a hard coded 
> list, but a text file that I can edit easily.
>
> The text file is three lines long and looks exactly like this:
>
> Reminder1,2009_10_28
> Reminder2,2009_11_01
> Reminder3,2009_11_15
>
> My program consists of the following code:
> ============
> #]------------------[import modules]------------------[
> from time import strftime, mktime, localtime
> from WConio import textcolor
> #]--------------------------------------------------------[
> #]------------------[define functions]------------------[
> def read_reminders():
>    print "\nReading text file into program: reminders.txt"
>    text_file = open("reminders.txt","r")
>    reminders = [line.strip().split("'") for line in text_file]
>    text_file.close()
>    print reminders
> #
> def get_computer_date():
>    #Get today's date from the computer
>    todays_date = strftime("%Y_%m_%d")
>    return todays_date
> #
> def color_print(strings):
>    #Change the text color in the WinXP dos shell
>    #The way to use:
>    #color_print([("string",color number),\
>    #(str(variable),color number),(etc)])
>    for string in strings:
>        textcolor(string[1])
>        print string[0],
> #
> def change_to_julian(reminder_date):
>    #Receives the year, month, and day
>    #in the form of a single string (2009_10_15)
>    #and changes it into three different int
>    #variables.  Then take those three variables
>    #and append six zeros and change into a
>    #julian date.
>    date = []
>    date = reminder_date.split("_")
>    year = int(date[0])
>    month = int(date[1])
>    day = int(date[2])
>    timetuple = (year, month, day) + ( (0,) * 6 )
>    unixtime = mktime(timetuple)
>    timetuple = localtime(unixtime)
>    print days_left(timetuple[7])
>    # [7] is the number of julian-date field of
>    #the unixtime tuple.
>    return days_left(timetuple[7])
> #
> def days_left(julian_date):
>    #This function calculates the days left
>    #until a reminder.  If the days left are
>    #greater than 0 it will print normally.
>    #If it is -1 then it will print differently.
>    #Also if it is greater than -1 it will print
>    #yet again differently.
>    days_until_reminder = julian_date - localtime().tm_yday
>    if days_until_reminder > 0:
>        color_print ([("There 
> are",7),(str(days_until_reminder),4),("days left until this 
> reminder.",7),("\n",7)])
>    elif days_until_reminder == -1:
>        color_print ([("\tYou have missed this reminder 
> by",4),(str(days_until_reminder*-1),4),("day!",4),("\n",7)])
>        color_print [("  
> ------------------------------------------------------------------------",4),("\n",7)]) 
>
>    else:
>        color_print ([("\tYou have missed this reminder 
> by",4),(str(days_until_reminder*-1),4),("days!",4),("\n",7)])
>        color_print [("  
> ------------------------------------------------------------------------",4),("\n",7)]) 
>
> print
> #
> def compare_reminders(todays_date):
>    #This function compares the reminders
>    #to the computer date.
>    #It has three different paths:
>    # 1.Matches today's date
>    # 2.The reminder date has already
>    #  passed by
>    # 3.The reminder date is yet to
>    #  come.
>    #After determining which it is it will
>    #access the change_to_julian and
>    #days_left functions.
>    #reminders.sort()
>    color_print ([(" 
> [-------------------------------------------------------------------------]",4),("\n",7)]) 
>
>    index = 0
>    while index < len(reminders):
>        if todays_date == reminders[index][1]:
>            print
>            color_print [("  
> ------------------------------------------------------------------------",4),("\n",7)]) 
>
>            print "Today's reminder is: 
> ",reminders[index][0],"on",reminders[index][1]
>            color_print ([("\t\tTake care of this reminder 
> immediately",2),("\n",7)])
>        elif todays_date > reminders[index][1]:
>            print
>            print "Whoops, you missed the following 
> reminder.",reminders[index][0],"on",reminders[index][1]
>            change_to_julian(reminders[index][1])
>        else:
>            print
>            print "Your upcoming reminders are: 
> ",reminders[index][0],"on",reminders[index][1]
>            change_to_julian(reminders[index][1])
>        index = index + 1
>    color_print ([(" 
> [-------------------------------------------------------------------------]",4),("\n",7)]) 
>
> #]--------------------------------------------------------[
> #]-------------------[Main Program]-------------------[
> read_reminders()
> print reminders
> compare_reminders(get_computer_date())
> pause_it = raw_input("Press a key to end: ")
> #]--------------------------------------------------------[
> ============
> Could someone explain to me why my read_reminders function retrieves 
> the information, but cannot process that information?
>
> When I try and run the program I get the following error message:
> ============
> Reading text file into program: reminders.txt
> [['Reminder1,2010_10_15'], ['Reminder2,2010_11_01'], 
> ['Reminder3,2010_11_15']]
> Traceback (most recent call last):
>    File "reminders.py", line 182, in <module>
>        print reminders
> NameError: name 'reminders' is not defined
> ============
>
> Thanks in advance for your help,
>
> Katt
>
>
The function read_reminders() doesn't return anything, so once it's 
done, those reminder items are gone.  It printed them, then forgot them.

Similarly, compare_reminders() tries to work on reminders, when it was 
not passed the data either.

You need to add a return statement to read_reminders(), and when you 
call it, you need to save it somewhere.  Then you can pass it to the 
compare_reminders() function so it has something to compare with.

Once you get that sorted out, another bug that's already apparent is 
that you're trying to split the line on quotes, when it uses commas 
between fields on each line.

DaveA