[[Category:OPS435-Python]][[Category:rchan]]
= Overview =
You have successfully design designed an algorithm to compute the date which is '''n''' day before or after a given date. You have also successfully implement implemented your algorithm using the Python language by identify identifying the functions that are need needed to perform the computation.
In this assignment, you are going to re-implement the algorithm you have for assignment 1 using python class. You are going to create a new programmer-define object call called Date with the appropriate data attributes and function attributes to support the necessary manipulation of '''date ''' object needed to implement your algorithm for assignment 1.
Your python script must follow the following coding guide:
** __init__(self): Date object constructor
** __repr__(self): return date object as a string in "yyyy-mm-dd" format
** __str__(self): return date object as a string in "yyyy:/mm:/dd" format
* Supporting function:
** days_to_time(): convert an integer which is n days from epoch (Jan 1, 1970) to a corresponding date object.
== Authorship Declaration ==
All your Your Python code for this assignment the Date class and its associated functions must be placed in a <font color='red'><b><u>single source python file</u></b></font>. Please include the following declaration <b><u>as part of the docstring</u></b> in your Python source code file (replace "Student Name" with your own name):
<source>OPS435 Assignment 2P - Fall 2019
Program: a1_[student_id].py (replace student_id with your Seneca User name)
== Tests and Test results ==
You must name your class definition python script for Date as <code>a2_class.py</code>. The following test scripts tests in an interactive python sessions are for testing your class definition. The assignment test scripts can script called "checkA2P.py" should be used to test the date objects created by using once your Date classpasses all the interactive tests.
Please review those tests that failed and try to fix it in your class definition to address any bugs you may have.
=== Test for operator overloading '+' and '-' ===
: <source lang="python">
>>> d1
2019-11-07
>>> d2
2019-11-14
>>> d1 - d2
-7
>>> d2 - d1
7
>>> d2 = Date(2019,2,28)
>>> d2
2019-02-28
>>>
</source>
== Script structure and sample template ==
Your code should all be in a single python file with at least the functions mentioned above: dbda(), after(), and before(). To earn the maximum mark, you should also create additional functions into your algorithm, e.g.: leap_year(), days_in_mon, valid_date(), usage(), etc
The following is a brief description of each function:
* The dbda() function should be the main function of your script. The dbda() function will take a date in "YYYY/MM/DD" format, a positive or negative integer, and return a date either before or after the given date according to the value of the given integer in the same format. Your dbda() function should delegate the actual calculation of the target date to either the after() function or the before() function.
* The before() function will take a date in "YYYY/MM/DD" format and return the date of the previous day in the same format.
* The after() function will take a date in "YYYY/MM/DD" format and return the date of the next day in the same format. Next paragraph is a sample python code for the after() function. To earn the maximum possible mark for the assignment, you should modify the sample after() function to make use of the days_in_mon() function.
* The leap_year() function will take a year in "YYYY" format, and return True if the given year is a leap year, otherwise return False.
* The valid_date() function will take a date in "YYYY/MM/DD" format, and return True if the given date is a valid date, otherwise return False plus an appropriate status message. The valid_date() function should make use of the days_in_mon() function.
* The days_in_mon() function will take a year in "YYYY" format, and return a dictionary object which contains the total number of days in each month for the given year. The days_in_mon() function should make use of the leap_year() function.
* The usage() function will take no argument and return a string describing the usage of the script.
<pre>
#!/usr/sbin/env python3
''' docstring
'''
import ...
def after(today):
....
return next_day
def before(today):
....
return previous_day
....
def dbda(date,days):
...
setup loop:
call after() or before() as appropriate
return target_day
if __name__ == "__main__":
.. processing command line arguments ..
.. call dbda()
...
.. output the result
</pre>
=== Sample code for the after() function ===
<pre>
# Return the date in YYYY/MM/DD after the given day
#
def after(today):
if len(today) != 10:
return '0000/00/00'
else:
str_year, str_month, str_day = today.split('/')
year = int(str_year)
month = int(str_month)
day = int(str_day)
lyear = year % 4
if lyear == 0:
feb_max = 29 # this is a leap year
else:
feb_max = 28 # this is not a leap year
lyear = year % 100
if lyear == 0:
feb_max = 28 # this is not a leap year
lyear = year % 400
if lyear == 0:
feb_max = 29 # this is a leap year
tmp_day = day + 1 # next day
mon_max = { 1:31, 2:feb_max, 3:31, 4:30, 5:31, 6:30, 7:31, 8:31, 9:30, 10:31, 11:30, 12:31}
if tmp_day > mon_max[month]:
to_day = tmp_day % mon_max[month] # if tmp_day > this month's max, reset to 1
tmp_month = month + 1
else:
to_day = tmp_day
tmp_month = month + 0
if tmp_month > 12:
to_month = 1
year = year + 1
else:
to_month = tmp_month + 0
next_date = str(year)+"/"+str(to_month).zfill(2)+"/"+str(to_day).zfill(2)
return next_date
</pre>
= Normal task =
Your script must be able to take two dates both in "YYYY/MM/DD" format and output the number of days between the given two dates.
e.g.
* Calculate the number of days between "2018/03/01" and "2019/03/01"
python3 a1_rchan.py 2018/03/01 2019/03/01
365
* Calculate the number of days between "2019/03/01" and "2018/03/01"
python3 a1_rchan.py 2019/03/01 2018/03/01
365
= Deliverable =
== Create a private repository on github.com under your account ==
* name the repository as 'ops435-a1'a2p* invite 'rayfreeping' as one of the collaborator to your 'ops435-a1a2p' repository
* use this repository for developing the and keeping track of the following text/source code files:
** the algorithm for assignment 1 named "a1_algorithmThe readme.md file to show your progress. Add entry whenever you update any files in this repository.txt"** the python script for assignment 1 class definition named "a1_[seneca-id]a2_class.py"** the test results produce by the assignment checking script "checkA1checkA2P.py". Name it as a1_resultsa2p_results.txt
= Rubric =
| Program Authorship Declaration ||5 ||
|-
| Program usage || 5 |||-| Program Options --step class block || 5 ||
|-
| after__init__() function method || 5 ||
|-
| before__str__() function method || 15 5 ||
|-
| dbda__repr() function method || 10 5 ||
|-
| script level docstring '+' operator || 5 10 ||
|-
| leap_year() function '-' operator || 5 10 ||
|-
| valid_datetomorrow() function method || 5 10 ||
|-
| days_in_monyesterday() function method || 5 10 ||
|-
| usageday_of_week() function || 5 ||
|-
| Algorithm docstring ||15||
|-
| github.com repository||15||
Please submit the following files to blackboard by the due date:
* your algorithm (step-by-step instruction for solving the computation problem for this assignment in the English language), name the file as 'a1_algorithm.txt'* your python script, name the file as 'a1_[seneca-id]a2_class.py'* the output of the checking script checkA1checkA2P.py, name the file as 'a1_resultsa2p_results.txt'* the 'git log' output for your own repository 'ops435-a1a2p' on github.com, name the file as 'a1_gitloga2p_gitlog.txt'