this is the assigment outline but i keep getting the error the code is ant the b
ID: 3830497 • Letter: T
Question
this is the assigment outline but i keep getting the error the code is ant the buttom and the error is the last part.
CS 112, Lab 13 – Exercise – Classes, Exceptions
Due: Moday May 1st, 11:59pm
Files:
Create your own file with our convention (userID_2xx_L13.py).
You should download the tester file from Piazza and run it as always:
python3 tester13L.py yourfile.py just these classes
o Note: you can only use three class names as the targeted tests for this lab:
Course testing everything with Course class w/o exception behavior
Transcript testing everything with Transcript class w/o exception behavior, must have Course class implemented
CourseError testing CourseError class and the exception behavior of Course class and Transcript class
As this is an Exercise, you can read any and all materials, ask us questions, talk with other students, and learn however you best learn in order to solve the task. Just create your own solution from those experiences, and turn in your work.
Classes allow us to define entirely new types. We might think of each type in Python as a set of values, and we use a class declaration to describe how to build and interact with all the values of this brand new type. We will often need at minimum a constructor (telling us what instance variables to always create), __str__ method (telling Python how to represent the thing as a string), and then any extra methods that we deem useful ways of interacting with the new values.
Turning It In
Add a comment at the top of the file that indicates your name, userID, G#, lab section, a description of your collaboration partners, as well as any other details you feel like sharing. Please also mention what was most helpful for you. Once you are done, run the testing script once more to make sure you didn't break things while adding these comments. If all is well, go ahead and turn in just your one .py file you've been working on over on BlackBoard to the correct lab assignment. We have our own copy of the testing file that we'll use, so please don't turn that in (or any other extra files), as it will just slow us down.
What can I use?
You may NOT import any module. There are no further restrictions – use this time to learn how to create classes and create objects of those classes.
Grading Rubric
Pass shared test cases 4x25 (zero points for hard-coding)
----------------------------------- TOTAL: 100
Task 1 - Course
A Course represents a specific course record as those appeared on your transcript.
class Course: Define the Course class.
def __init__(self, number, credit, grade): Course constructor. All three parameters must be stored to instance variables of the same names (number, credit, and grade).
o number :: str. Represents course number, like "CS112" or "MATH113". o credit :: int. Represents credit hours. You can assume it will always be a positive integer. o grade :: str. Represents letter grade. Can only be 'A','B','C','D','F', or 'IP'. If the provided grade is not one of these (for example, grade == "K"), then raise a CourseError with the message "bad grade 'K'". (You can skip this exception-raising part until later).
def __str__(self): returns a human-centric string representation. If number=="CS112", credit==4, and grade=="A", then the returned string must be "CS112: credit 4, grade A" (note the four single spaces).
def __eq__(self,other): we want to check that two courses are equal (our self and this other course). We compare each instance variable like so (this is the definition!) return self.number==other.number and self.credit==other.credit and self.grade==other.grade
def is_passing(self): checks whether this course has passed or not according to grade. Return False if the grade is 'F' or 'IP'; return True otherwise.
Task 2 - Transcript
This represents a group of Course values as a list (named courses). We can then dig through this list for useful course information and calculations by calling the methods we're going to implement.
class Transcript: Define the Transcript class.
def __init__(self): Transcript constructor. Create the only instance variable, a list named courses, and initialize it to an empty list. This means that we can only create an empty Transcript and then add items to it later on.
def __str__(self): returns a human-centric string representation. We'll choose a multi-line representation (slightly unusual) that contains "Transcript:" on the first line, and then each successive line is a tab, the str() representation of the next Course object in self.courses, and then a newline each time. This means that the last character of the string is guaranteed to be a newline (regardless of whether we have zero or many Course values).
def __eq__(self,other): we want to check that two transcripts are equal (our self and this other transcript). The only things that we need to compare are their lists of courses. Note: you can compare two lists l1 and l2 directly as l1==l2 but this will rely on your implementation of __eq__() for Course class since we are comparing two lists of courses.
def add_course(self, course): append the argument course to the end of self.courses. In order to ensure every course number is unique, if our transcript already has a course of the same number (for example 'ENGH101'), raise a CourseError with the message "duplicate course number 'ENGH101'". (You can skip this exception-raising part until later). • def course_by_number(self, number): Look through all storedCourse objects in self.courses.
Return the Course object whose number matches the number argument. If no match, return None. You can assume that every course number is unique in a transcript.
def course_by_grade(self, grade): search through self.courses in order, return a list of Course object in this Transcript that is of this grade. If no match, return an empty list. • def total_passing_credit(self): Look through all stored Course objects in self.courses.
Return total credit hours of all courses that have a passing grade.
Task 3 – CourseError
The CourseError class extends the notion of an Exception (note the (Exception) part of the class signature line). We're making our own exception that stores a single string message.
class CourseError(Exception): Define the CourseError class to be a child of Exception class (by putting Exception in the parentheses as shown).
def __init__(self,msg): Constructor. Store msg to an instance variable named msg.
def __str__(self): human-centric representation of CourseError is just self.msg
If you skipped the two exception-raising parts above, you should now go back and add those checks/raises. The test cases for CourseError will go back and check if those parts correctly did so.
this id the code
class Course:
def __init__(self, number, credit, grade):
self.number = number
self.credit = credit
gradeList = ['A', 'B', 'C', 'D', 'F', 'IP']
if grade in gradeList:
self.grade = grade
else:
raise CourseError("bad grade '" + str(grade) + "'")
def __str__(self):
return self.number + ": credit " + str(self.credit) + ", grade " + self.grade
def __eq__(self,other):
return self.number==other.number and self.credit==other.credit and self.grade==other.grade
def is_passing(self):
return not (self.grade == 'F' or self.grade == 'IP')
class Transcript:
def __init__(self):
self.courses = []
def __str__(self):
transcript = "Transcript: "
for course in self.courses:
transcript += str(course) + " "
return transcript
def __eq__(self,other):
return self.courses == other.courses
def add_course(self, course):
for crs in self.courses:
if course == crs:
raise CourseError("duplicate course number '" + course.number + "'")
self.courses.append(course)
def course_by_number(self, number):
for course in self.courses:
if course.number == number:
return course
return None
def course_by_grade(self, grade):
grade_list = []
for course in self.courses:
if course.grade == grade:
grade_list.append(course)
return grade_list
def total_passing_credit(self):
total_hours = 0
for course in self.courses:
if course.is_passing():
total_hours += course.credit
return total_hours
class CourseError(Exception):
def __init__(self, msg):
self.msg = msg
def __str__(self):
return self.msg
c1 = Course("CS112",4,"A")
print(c1.is_passing())
c2 = Course("ENGH101",3,"B")
print (c1==c2)
c3 = Course("MATH113",4,"IP")
t = Transcript()
print(str(t))
t.add_course(c1)
t.add_course(c2)
t.add_course(c3)
print(str(t))
t.add_course(Course("GAME101",3,"A"))
t.course_by_number("CS112")
print(t.course_by_number("CS112"))
t.course_by_number("CS114")
print(t.course_by_number("CS114"))
ans = t.course_by_grade("A")
print(len(ans))
c = Course("CS101",2,"Y") # this should raise a CourseError
error that i keep getting
C:UserskomalDesktop>tester.py sshah38_223_L13.py
True
False
Transcript:
Transcript:
CS112: credit 4, grade A
ENGH101: credit 3, grade B
MATH113: credit 4, grade IP
CS112: credit 4, grade A
None
2
Exception in loadingsshah38_223_L13.py:
bad grade 'Y'
Run your file without the tester to see the details
========================================
Traceback (most recent call last):
File "C:UserskomalDesktop ester.py", line 554, in <module>
main()
File "C:UserskomalDesktop ester.py", line 348, in main
print(" Test cases: %d/%d passed" % (passed1,tried1) )
TypeError: %d format: a number is required, not NoneType
C:UserskomalDesktop>
Explanation / Answer
Firstly you doesn't seem to have Exception class
here is full code:
class CourseError(Exception):
def __init__(self, msg):
self.msg = msg
def __str__(self):
return self.msg
class Course:
def __init__(self, number, credit, grade):
self.number = number
self.credit = credit
gradeList = ['A', 'B', 'C', 'D', 'F', 'IP']
if grade in gradeList:
self.grade = grade
else:
raise CourseError("bad grade '" + str(grade) + "'")
def __str__(self):
return self.number + ": credit " + str(self.credit) + ", grade " + self.grade
def __eq__(self,other):
return self.number==other.number and self.credit==other.credit and self.grade==other.grade
def is_passing(self):
return not (self.grade == 'F' or self.grade == 'IP')
class Transcript:
def __init__(self):
self.courses = []
def __str__(self):
transcript = "Transcript: "
for course in self.courses:
transcript += str(course) + " "
return transcript
def __eq__(self,other):
return self.courses == other.courses
def add_course(self, course):
for crs in self.courses:
if course == crs:
raise CourseError("duplicate course number '" + course.number + "'")
self.courses.append(course)
def course_by_number(self, number):
for course in self.courses:
if course.number == number:
return course
return None
def course_by_grade(self, grade):
grade_list = []
for course in self.courses:
if course.grade == grade:
grade_list.append(course)
return grade_list
def total_passing_credit(self):
total_hours = 0
for course in self.courses:
if course.is_passing():
total_hours += course.credit
return total_hours
c1 = Course("CS112",4,"A")
print(c1.is_passing())
c2 = Course("ENGH101",3,"B")
print (c1==c2)
c3 = Course("MATH113",4,"IP")
t = Transcript()
print(str(t))
t.add_course(c1)
t.add_course(c2)
t.add_course(c3)
print(str(t))
t.add_course(Course("GAME101",3,"A"))
t.course_by_number("CS112")
print(t.course_by_number("CS112"))
t.course_by_number("CS114")
print(t.course_by_number("CS114"))
ans = t.course_by_grade("A")
print(len(ans))
c = Course("CS101",2,"Y") # this should raise a CourseError
# pastebin code link: https://pastebin.com/zaKDAAKs
Now about the error you are getting, you test is expecting a int and its getting a None,
But this really can't be solved without your providing your full tester class. Put your tester in some online source and share link in comment and I will fix your errors so that all test pass (assuming tester is something instructor provided)
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