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

[Katt]

>> 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
>> _______________________________________________
>> Tutor maillist  -  Tutor at python.org
>
> #]-------------------[Main Program]-------------------[
> reminders = read_reminders()

This is the item that I was forgeting.  Originally I tried to use the 
"return" in my function, but left out what I was returning.  However if I 
did not notice this one line I would have continued to be stuck.  I guess I 
thought all you would have to do is call the function and it would know to 
make the return information into a global list.

===================================================
> It appears you did not return the list of reminders that you extracted
> in the "read_reminders" function, but simply printed them from inside
> that function.

Yes, originally I did this to find out how python would read the 
information.  Kind of an error check type thing.

> called "reminders", you  should be able to access the list in your
> global namespace.

If I hadn't paid attention to the end of Vince's post I would have not 
understood this as I am unfamiliar with some of the vocabulary (i.e.: global 
namespace).

> Also, on a side note, you can greatly improve the readability of your
> code by using the triple-quote style for multi-line docstrings inside
> functions (rather than the hash comment marks). I tend to use hash
> marks for one-line/inline comments, since they can really become an
> eyesore (at least IMHO) when used too liberally.
>
> Also, Python's whitespace and code formatting conventions can handle a
> lot of the "documentation" for you. For instance,  module imports are
> typically always performed at the top of a script, so it's reasonable
> to expect that others reading your code will understand you're
> importing some modules.
>
> Much of this spelled out in PEP's 8 (style guide) and 257 (doc strings):
>
> http://www.python.org/dev/peps/pep-0008/
> http://www.python.org/dev/peps/pep-0257/

I will make sure to check these out soon so that my comments are more 
readable.

==============================================

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

Sorry, about that.  I got lazy and just replied to a tutor message I had in 
my inbox.  Will make sure not to let that happen again.

> 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.

Missed that one.  Once I changed this everything clicked into place.

 Thank you Alan G.,Vince S., Serdar T., and Dave A. for your help.  I don't 
think I woud have got this on my own.  It is true that sometimes you can't 
see the answer when it is staring you in the face.

Thanks again,

Katt