Calendar problem

[KomodoM]

Hi! I'm trying to program a monthly calendar.... but I can't get the weekdays for the nth day
of the year right... my problem is written further down in the code...

from time import *

class Calendar:
    '''Skapar en kalender för varje månad'''
    def __init__(self, year, month):
        self.year = year
        self.month = month
from time import *

class Calendar:
    '''Skapar en kalender för varje månad'''
    def __init__(self, year, month):
        self.year = year
        self.month = month


    def leap_year(self, year):
        '''Metod som tar reda på om året är ett skottår'''
        if (year % 4 == 0) and not(year % 100 == 0)or (year % 400 == 0):
            return year
        else:
            return None


    def weekday(self, year, weekday):
        '''Metod som tar fram veckodagen för varje dag.'''
        d = weekday
        if year:
            d += (year-1900) * 365
        for i in range(1900, year):
            if self.leap_year(i):
                d += 1

My problem starts here..
#d = the amount of days from year 1900 until chosen year. Now I want each of these days to be given a weekday number from 0-6...starting from day 1 year 1900 which is a monday 
(weekdays[0]), until day d which is the last day of the chosen year.... How do i do this? I have tried some things here: But I know they don't really work..can someone please help me?!

        for i in range(0, d):
            if (i % 7 == 0)or (i == 0):
                i -= i
                while i < 7:
                    i += 1
                    w = weekdays[i-1]
                    return w
            and if (i % 7 == 0) and (i >= (d-6)):
                print weekdays[(d-i)]
                    


#Mainprogram

months = ['januari', 'februari', 'mars', 'april', 'maj', 'juni', 'juli', 'augusti',\
                       'september', 'oktober', 'november', 'december']

weekdays = ['Må', 'Ti', 'On', 'To', 'Fr', 'Lö', 'Sö']

days = [31,28,31,30,31,30,31,31,30,31,30,31]


def write_calendar(days_until):
    '''Skriver ut kalendern'''
    


def menu():
    '''Skriver ut menyn samt anropar metoder och funktioner för respektive alternativ.'''

    choice = None
    while choice != '3':
        print \
        '''
        (1) See this months calendar
        (2) Choose year and month
        (3) End
        '''
        choice = raw_input('Which alternative do you choose?')

        if choice == '1':
            today = localtime()
            this_month = Calendar(today[0], today[1])
            this_month.leap_year(today[0])
            this_month.weekday(today[0], 0)
            a = 0
            for i in range(0, (today[1]-1)):
                a += days[i]
           
            
        
        elif choice =='2':
            chosen_year = input(What year would you like to see?')
            chosen_month = input(What month would you like to see?')
            your_choice = Calendar(chosen_year, chosen_month)
            your_choice.leap_year(chosen_year)
            your_choice.weekday(chosen_year, 0)
            a = 0
            for i in range(0, (chosen_month-1)):
                a += days[i]
            

menu()

[BearofNH]

Hi! I'm trying to program a monthly calendar.... but I can't get the weekdays for the nth day
of the year right...

Have you looked far enough into the time module? The tm_wday element of the struct_time is exactly what you want.

Or is there some reason you can't use that?

[KomodoM]

Have you looked far enough into the time module? The tm_wday element of the struct_time is exactly what you want.

Or is there some reason you can't use that?

Haven't looked there for it, but I have a task that says I should use the 1 of january year 1900 as a constant in the program to calculate the weekdays for all other days...

[woooee]

Have you tested the code below to see if it does what you think. I don't know myself but it is unclear at best and if you have to explain it, will you be able. The following untested code breaks it down into steps

def leap_year(self, year):
   if (year % 4 == 0) and not(year % 100 == 0)or (year % 400 == 0):
#   
##------- Breaking it down into steps  ---------------------------
   # eliminate this first
   if year % 400 == 0:     ## is leap year
      return 1
   ##   has to be divisible by 4
   if year % 4 == 0:
      # if divisible by 4 and 100 then it is not a leap year
      if (year % 100 == 0):
         return 0
      else:
         return 1
   return 0     ## not a leap year-->not divisible by 4 or 400

As for the days of the week, is the variable d the number of days from 1900? And is the first day in d --> weekday=0, and d==2 --> weekday=1, so then d==8 --> weekday=0 = start over again? If so you should be able to use divmod(d-1, 7) with the remainder being the day of the week.

[woooee]

For those of us who were around before there were canned date/time libraries, Zeller's Congruence was common knowledge http://en.wikipedia.org/wiki/Zeller's_congruence but it would have to be modified by comparing the actual day of the week of 01-01-1900 and what you would have to add or subtract to get 01-01-1900 to be a Monday.

[woooee]

I just noticed this. After the final line of this snippet, i will always be zero if it was greater than zero, and -(2i) if it was less than zero. Is that what you are trying to do?

for i in range(0, d):
       if (i % 7 == 0)or (i == 0):
                i -= i

[vegaseat]

You might be able to use this ...

# this gives daily info:
# takes care of leap-years too

import datetime as dt

wday = ['Monday', 'Tuesday', 'Wednesday', 'Thursday',
    'Friday', 'Saturday', 'Sunday']

start = dt.date(1900, 1, 1)

oneday = dt.timedelta(days=1)

# test it for the first 370 days
for x in range(370):
    print start.year, start.month, start.day, wday[start.weekday()]
    start += oneday

[KomodoM]

Have you tested the code below to see if it does what you think. I don't know myself but it is unclear at best and if you have to explain it, will you be able. The following untested code breaks it down into steps

def leap_year(self, year):
   if (year % 4 == 0) and not(year % 100 == 0)or (year % 400 == 0):
#   
##------- Breaking it down into steps  ---------------------------
   # eliminate this first
   if year % 400 == 0:     ## is leap year
      return 1
   ##   has to be divisible by 4
   if year % 4 == 0:
      # if divisible by 4 and 100 then it is not a leap year
      if (year % 100 == 0):
         return 0
      else:
         return 1
   return 0     ## not a leap year-->not divisible by 4 or 400

As for the days of the week, is the variable d the number of days from 1900? And is the first day in d --> weekday=0, and d==2 --> weekday=1, so then d==8 --> weekday=0 = start over again? If so you should be able to use divmod(d-1, 7) with the remainder being the day of the week.

The leap year method works as it should.. and yes I want the days d to be given numbers from 0-6 just like you explained above......how does divmod(d-1, 7) work?

[KomodoM]

I just noticed this. After the final line of this snippet, i will always be zero if it was greater than zero, and -(2i) if it was less than zero. Is that what you are trying to do?

for i in range(0, d):
       if (i % 7 == 0)or (i == 0):
                i -= i

I was trying to split the days up into weeks, and then by saying every seventh day will be zero, I could give every day a number from 0-6.... but this just keeps looping, and I don't know how to do to make it stop when i == d

[KomodoM]

You might be able to use this ...

# this gives daily info:
# takes care of leap-years too

import datetime as dt

wday = ['Monday', 'Tuesday', 'Wednesday', 'Thursday',
    'Friday', 'Saturday', 'Sunday']

start = dt.date(1900, 1, 1)

oneday = dt.timedelta(days=1)

# test it for the first 370 days
for x in range(370):
    print start.year, start.month, start.day, wday[start.weekday()]
    start += oneday

I tried something like this... but I don't get it to work...

from time import *
import datetime as dt
start = dt.date(1900, 1, 1)
oneday = dt.timedelta(days=1)

class Calendar:
    '''Skapar en kalender för varje månad'''
    def __init__(self, year, month):
        self.year = year
        self.month = month


    def leap_year(self, year):
        '''Metod som tar reda på om året är ett skottår'''
        if (year % 4 == 0) and not(year % 100 == 0)or (year % 400 == 0):
            return year
        else:
            return None


    def weekday(self, year, days):
        '''Metod som tar fram veckodagen för varje dag.'''
        d = days
        if year:
            d += (year-1900) * 365
        for i in range(1900, year+1):
            if self.leap_year(i):
                d += 1
        print d
        for i in range(0, d):
            print weekdays[start.weekday()]
            start += oneday