CSC111 Homework 9 2015
--D. Thiebaut (talk) 22:47, 30 March 2015 (EDT)
This assignment is due the evening of Tuesday 4/7/15, at 11:55 p.m.
Contents
Problem #1: Lost Cat
(image from nicepixy.net)
The program below is missing its class! And it is also missing its documentation! It used to contain a class defined, with methods and member variables, and a fully developped documentation, but unfortunately all of them got erased.
We do have the output of a run of the program, though, when it still had its class definition. Both the incomplete code and the output are shown below.
#
# missing class goes here...
#
def getNewCat():
print( "\nPlease enter the information for the new cat:")
name = input( "Cat name? " )
age = int( input( "Age, in years? " ) )
vac = input( "Vaccinated (Y/N)? " ).strip().lower()
vac = vac in ['y', 'yes']
neut = input( "Neutered (Y/N)? " ).strip().lower()
neut = neut in ['y', 'yes' ]
breed= input( "Breed? " ).strip()
return Cat( name, age, vac, neut, breed )
def display( catList, caption ):
print( "\n\n"+caption )
print( "=" * len( caption ) )
for cat in catList:
print( cat )
def main():
#comments below are for debugging purpose
#text="""Minou, 3, Yes, Yes, stray
# Max, 1, Yes, No, Burmese
# Gizmo, 2, No, No, Bengal
# Garfield, 4, Yes, Yes, Orange Tabby"""
file = open( "cats.csv", "r" )
text = file.read()
file.close()
for line in text.split( "\n" ):
words = line.strip().split( "," )
if len( words ) != 5:
continue
name, age, vaccinated, neutered, breed = words
age = int( age.strip() )
if vaccinated.strip().lower() == "yes":
vaccinated = True
else:
vaccinated = False
neutered = neutered.strip().lower() == "yes"
cat = Cat( name.strip(), age, vaccinated, neutered, breed.strip() )
try:
cats.append( cat )
except NameError:
cats = []
cats.append( cat )
display( cats, "List of cats:" )
vaccinatedNeuteredCats = []
for cat in cats:
if cat.isVaccinated() and cat.isNeutered():
vaccinatedNeuteredCats.append( cat )
display( vaccinatedNeuteredCats, "Vaccinated and neutered cats:" )
main()
Example cats.csv File
Minou, 3, Yes, Yes, stray Max, 1, Yes, No, Burmese Gizmo, 2, No, No, Bengal Garfield, 4, Yes, Yes, Orange Tabby
Corresponding Output
List of cats:
=============
Cat: Minou, age: 3, vaccinated, neutered (stray)
Cat: Max, age: 1, vaccinated, not neutered (Burmese)
Cat: Gizmo, age: 2, not vaccinated, not neutered (Bengal)
Cat: Garfield, age: 4, vaccinated, neutered (Orange Tabby)
List of cats with new addition:
===============================
Cat: Minou, age: 3, vaccinated, neutered (stray)
Cat: Max, age: 1, vaccinated, not neutered (Burmese)
Cat: Gizmo, age: 2, not vaccinated, not neutered (Bengal)
Cat: Garfield, age: 4, vaccinated, neutered (Orange Tabby)
Vaccinated and neutered cats:
=============================
Cat: Minou, age: 3, vaccinated, neutered (stray)
Cat: Garfield, age: 4, vaccinated, neutered (Orange Tabby)
- Question
Recreate the original program with its Cat class. Make sure that it will generate the same output shown above if fed the same cat information.
Document your code well, including the main(), getNewCat() and display() functions. Document the class using the same approach as in Part 2, below.
Store your program in a file called hw9_1.py and submit it to the Moodle HW9 PB1 section.
Problem #2: Of dogs and people...
(image from naturesmightypictures.blogspot.com)
Create a new program with the code below. Call it hw9_2.py.
#
class Person:
# a class containing 4 private member variables:
# - name of the person (string)
# - age (integer)
# - gpa (float)
# - major (string, uppercase)
# methods:
# getName(): returns the name of the person (string)
# getAge(): returns the age of the person (int)
# setAge(x): sets the age of the person to x (int)
# constructor: intializes a person with all fields
def __init__(self, n, a ):
self._name = n
self._age = a
# returns a string with the name and age.
def __str__( self ):
return "%s, %d years old" % ( self._name, self._age )
# returns the name
def getName( self ):
return self._name
# set the age to a new value x
def setAge( self, x ):
self._age = x
# returns the age of the person
def getAge( self ):
return self._age
class Dog:
# a class containing 2 private member variables:
# - name-tag of the dog (string)
# - whether the dog is vaccinated or not (boolean)
# methods:
# isVaccinated(): returns True if the dog is vaccinated, False otherwise
# getName(): returns the name-tag of the dog
# setName(x): sets the name-tag of the dog
# constructor
def __init__( self, tag, vaccinated ):
self._tag = tag
self._vaccinated = vaccinated
# default string representation for the dog
def __str__( self ):
if self._vaccinated==True:
return "%s (vaccinated)" % self._tag
return "%s (not vaccinated)" % self._tag
# isVaccinated: returns True if the dog is vaccinated, False otherwise
def isVaccinated( self ):
return self._vaccinated
# returns the name of the dog
def getNameTag( self ):
return self._tag
# changes the name-tag
def setNameTag( self, tag ):
self._tag = tag
class ListPeopleDog:
# a class that maintains a list of pairs. The first
# element of a pair is a Person object, the second a Dog object
# if the person doesn't have a dog, the second element of the pair is None
# Methods supported:
# isEmpty(): returns True if the list is empty, False othewise
# append( p, d ): appends a pair( person, dog) to the list
# getDogOf( name ): returns the dog object associated with the given person's name
# getOwnerOf( tag ): returns the person object associated with the given dog tag
# size( ): returns the number of pairs in the list
# getPersonDogAt( i ): returns the person object and the dog object located
# at Index i in the list.
# constructor
def __init__( self ):
self._L = []
# returns a string formatted as several lines, each representing
# a person and his/her dog.
def __str__( self ):
s = ""
for person, dog in self._L:
if dog==None:
s = s + str( person )+ " [No dogs]\n"
else:
s = s + str( person )+ " ["+str( dog ) +"]\n"
return s
# returns True if the list is empty. False otherwise.
def isEmpty( self ):
return len( self._L )==0
# add a new pair to the list
def append( self, person, dog ):
self._L.append( (person, dog) )
# returns the dog associated with the first person who's name is passed.
def getDogOf( self, name ):
name = name.strip().lower()
for person, dog in self._L:
if dog==None:
continue
if person.getName().lower() == name:
return dog
return None
# returns the person object associated with the first dog in the list with the
# tag passed as a parameter.
def getOwnerOf( self, name ):
name = name.strip().lower()
for person, dog in self._L:
if dog==None:
continue
if dog.getNameTag().lower()==name:
return person
return None
# returns the number of pairs in the list.
def size( self ):
return len( self._L )
# returns the person and dog located at Index i in the list.
def getPersonDogAt( self, i ):
if i < len( self._L ):
return self._L[i][0], self._L[i][1]
return None, None
# ================================================
# main
# ================================================
def main():
text = """Joe, 23, Fido, vaccinated
Debra, 30, Rex, not vaccinated
Frida, 10, Ralph, vaccinated
Maria, 21, Gizmo, vaccinated
Frank, 31, ,
Millie, 25, Maxi, not vaccinated"""
# create a new ListPeopleDog object
L = ListPeopleDog()
# parse the text and add it as people-dog pairs in the list
for line in text.split( "\n" ):
if len( line.split(',') ) != 4:
continue
name, age, tag, vacc = line.split(',')
name = name.strip()
age = int( age.strip() )
tag = tag.strip()
vacc = "not" not in vacc.lower()
if len( tag )==0:
L.append( Person(name, age), None )
else:
L.append( Person(name, age), Dog( tag, vacc ) )
# Display the list
for i in range( L.size() ):
p, d = L.getPersonDogAt( i )
if d != None:
print( p, "has a dog: ", d )
else:
print( p, "does not have a dog" )
main()
Your Assignment
- Without modifying any of the classes, make your program output
- the list of people who have unvaccinated dogs
- the list of people without dogs
- the oldest person who has a dog
An example of the output of the solution program is shown below:
Joe, 23 years old has a dog: Fido (vaccinated)
Debra, 30 years old has a dog: Rex (not vaccinated)
Frida, 10 years old has a dog: Ralph (vaccinated)
Maria, 21 years old has a dog: Gizmo (vaccinated)
Frank, 31 years old does not have a dog
Millie, 25 years old has a dog: Maxi (not vaccinated)
Debra, 30 years old has a non vaccinated dog called Rex
Millie, 25 years old has a non vaccinated dog called Maxi
Frank, 31 years old doesn't have a dog
The oldest person to own a dog is Debra, 30 years old and the dog is Rex (not vaccinated)
Store your program in a file called hw9_2.py and submit it to Moodle, in the HW9 PB2 section.
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