|
CS 3723 Programming Languages Fall 2014 | |
Homework 12. Time/Date Classes
| ||
Week 15-16: Dec 1 - 10
| ||
Submit following directions at:
submissions
and rules at:
rules.
Deadlines are:
|
| Date Example | |
|---|---|
| Python | Python and Output |
# date1.py: class for dates
mon = [None,"Jan","Feb","Mar","Apr",
"May","Jun","Jul","Aug",
"Sep","Oct","Nov","Dec"]
days = [0, 31, 28, 31, 30, 31, 30,
31, 31, 30, 31, 30, 31]
def check_date(y, m, d):
if m < 1 or m > 12 or d < 0 or d > 31 or y < 0:
return False
elif d > 0 and d <= days[m]:
return True
elif m == 2 and d == 29 and is_leap(y):
return True
else:
return False
### end of: check_date
def is_leap(y):
if y%400 == 0 or (y%4 == 0 and y%100 != 0):
return True
else:
return False
### end of: is_leap
class Date:
def __init__(self, y, m, d):
self.year = y
self.month = m
self.day = d
### end of: __init__
def __str__(self):
return mon[self.month] + \
" " + str(self.day) + \
", " + str(self.year)
### end of: __str__
def incr_day(self):
self.day +=1
if not (self.month == 2 and \
is_leap(self.year) and \
self.day == 29) and \
self.day > days[self.month]:
self.day = 1
self.incr_month()
### end of: incr_day
def incr_month(self):
self.month +=1
if self.month > 12:
self.month = 1
self.incr_year()
### end of: incr_month
def incr_year(self):
self.year += 1
### end of: incr_year
### end of: date1 class
def test_date(y, m, d):
date = Date(y, m, d)
print "Start Date: ", date, " "
date.incr_day()
print " Next day: ", date , " "
date.incr_day()
print " Next day: ", date , " "
date.incr_day()
print " Next day: ", date, "\n"
|
print "TEST ORDINARY DATES" test_date(2004, 4, 22) test_date(2013, 3, 30) test_date(2013, 4, 29) print "\nTEST YEAR END" test_date(2001, 12, 30) test_date(1999, 12, 30) print "\nTEST LEAP YEARS" test_date(2004, 2, 28) test_date(2001, 2, 27) test_date(2000, 2, 28) test_date(1900, 2, 27) test_date(2100, 2, 27) |
- Create a Time class: In the same file add another class Time that will keep track of hours, minutes, and seconds. This new class should be similar to the Date class. although simpler. In particular, it should have methods: __init__, __str__, incr_sec, incr_min, and incr_hour.
- Test your new Time class by itself:
Test it with code to instantiate time objects
and to test incrementing by seconds, including showing that
it correctly handles the end of a minute, the end of an hour, and the
end of 24 hours. For this part you should create test data
that prints the following. (You can do this in a way similar to
the test of Date above.)
Possible output TEST TIMES Start Time: 04:31:26 Next sec: 04:31:27 Next sec: 04:31:28 Next sec: 04:31:29 Start Time: 07:31:58 Next sec: 07:31:59 Next sec: 07:32:00 Next sec: 07:32:01 Start Time: 12:59:58 Next sec: 12:59:59 Next sec: 13:00:00 Next sec: 13:00:01 Start Time: 23:59:58 Next sec: 23:59:59 Next sec: 00:00:00 Next sec: 00:00:01
- Let Date inherit from the class object: This is trivial: replace "class Date:" with "class Date(object):". (The class "object" is at the root of all Python classes, whether explicitly defined or not. We need it explicitly here for the inheritance to work.)
- Change your Time class so that it inherits the Date class: Then Date is a superclass of Time, and Time is a subclass of Date. (In Java terms, Time extends Date, and in place of the Java "Time extends Date", Python writes "Time(Date)". The initializer for Time should now have 6 parameters, including the ones before, along with year, month, and day. These last three will be passed on into Date using the super method. [Again see the Chapter on Classes.]
- Alter the incr_hour method of the Time class: Change it so that in case an increment goes past hour 23, it will wrap around to hour 0 and increment to the next day.
- Test your version of Time that inherits
from Date:
You should test your program with
initial data that produces output looking something
like the following. (But not the "Comments".
You can do this in a way similar to
the test of Date above.)
Possible output Comments TEST TIME/DATE Start time: Jan 31, 2001 04:31:26 Next sec: Jan 31, 2001 04:31:27 Next sec: Jan 31, 2001 04:31:28 Next sec: Jan 31, 2001 04:31:29 Start time: Apr 22, 2004 23:59:58 Next sec: Apr 22, 2004 23:59:59 Next sec: Apr 23, 2004 00:00:00 Next sec: Apr 23, 2004 00:00:01 Start time: Jan 31, 2001 23:59:58 Next sec: Jan 31, 2001 23:59:59 Next sec: Feb 1, 2001 00:00:00 Next sec: Feb 1, 2001 00:00:01 Start time: Apr 30, 2004 23:59:58 Next sec: Apr 30, 2004 23:59:59 Next sec: May 1, 2004 00:00:00 Next sec: May 1, 2004 00:00:01 Start time: Feb 28, 2004 23:59:58 Next sec: Feb 28, 2004 23:59:59 Next sec: Feb 29, 2004 00:00:00 Next sec: Feb 29, 2004 00:00:01 Start time: Feb 28, 1900 23:59:58 Next sec: Feb 28, 1900 23:59:59 Next sec: Mar 1, 1900 00:00:00 Next sec: Mar 1, 1900 00:00:01 Start time: Feb 28, 2000 23:59:58 Next sec: Feb 28, 2000 23:59:59 Next sec: Feb 29, 2000 00:00:00 Next sec: Feb 29, 2000 00:00:01 Start time: Feb 28, 2001 23:59:58 Next sec: Feb 28, 2001 23:59:59 Next sec: Mar 1, 2001 00:00:00 Next sec: Mar 1, 2001 00:00:01 Start time: Dec 31, 2004 23:59:58 Next sec: Dec 31, 2004 23:59:59 Next sec: Jan 1, 2005 00:00:00 Next sec: Jan 1, 2005 00:00:01 Start time: Dec 31, 1999 23:59:58 Next sec: Dec 31, 1999 23:59:59 Next sec: Jan 1, 2000 00:00:00 Next sec: Jan 1, 2000 00:00:01
Next second Next hour Next day Next month Next day (leap year) Next month (not leap year) Next day (not leap year) Next month (leap year) Next year Next century
- The Python source showing the Date class and the Time class that inherits from Date.
- A run that produces the data shown in item 6 above. (In this case you should NOT submit any run that produces the data shown in item 2 above.)
- Whatever Python code you produced.
- The results of any runs. If your Date class runs by itself and produces results similar to those in item 2 above, it's important that you show this for part credit.