Transcript Python Classes Dr. Philip Cannata Dr. Philip Cannata Python class code for Aristotle example – animal and cat classes class animal(object) : num_eyes.

Python Classes
Dr. Philip Cannata
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Dr. Philip Cannata
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Python class code for Aristotle example – animal and cat classes
class animal(object) :
num_eyes = 2
num_teeth = 0
num_children = 0
def __init__(self, num_t, num_kids) :
self.num_teeth = num_t
self.num_children = num_kids
a1 = animal(100,5)
print a1.num_eyes, a1.num_teeth, a1.num_children
print a1
class cat(animal) :
color_fur = "brown"
len_tail = 3
def __init__(self, fur, tail) :
self.color_fur = fur
self.len_tail = tail
my_cat = cat("yellow", 4)
my_cat.num_teeth = 28
my_cat.num_children = 4
print my_cat.num_eyes, my_cat.num_teeth, my_cat.num_children, my_cat.color_fur
Dr. Philip Cannata
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Python class code with “super” in constructor for Aristotle example - animal and cat classes
class animal(object) :
num_eyes = 2
num_teeth = 0
num_children = 0
def __init__(self, num_t, num_kids) :
self.num_teeth = num_t
self.num_children = num_kids
a1 = animal(100,5)
print a1.num_eyes, a1.num_teeth, a1.num_children
print a1
class cat(animal) :
def __init__(self, num_t, num_kids, fur, tail) :
super(cat,self).__init__(num_t, num_kids)
self.color_fur = fur
self.len_tail = tail
my_cat = cat( 34, 2, 23,2)
print my_cat.num_eyes, my_cat.num_teeth, my_cat.num_children, my_cat.color_fur, my_cat.len_tail
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Python class code for Aristotle example – animal, cat, human, and knowledge classes
class animal() :
num_eyes = 2
num_teeth = 24
def __init__(self, e, t) :
self.num_eyes = e
self.num_teeth = t
class cat(animal) :
def __init__(self, c, l) :
self.fur_color = c
self.len_tail = l
socrates = human(s="Golf")
print socrates.num_eyes, socrates.num_teeth, socrates.IQ, socrates.sports_played
class knowledge() :
grammatical = ''
math = ''
human = []
def __init__(self, g, m) :
self.grammatical = g
self.math = m
a1 = animal(2, 30)
print a1.num_eyes, a1.num_teeth
my_cat = cat("yellow", 4)
print my_cat.num_eyes, my_cat.num_teeth, my_cat.fur_color, my_cat.len_tail
class human(animal) :
IQ = 100
sports_played = "Football"
knowledge = []
def __init__(self, s, i = 100) :
self.IQ = i
self.sports_played = s
Dr. Philip Cannata
socrates_Knowledge = knowledge('Some Greek language knowledge', "Some
math smarts")
socrates.knowledge.append(socrates_Knowledge)
socrates_Knowledge.human.append(socrates)
print socrates.num_eyes, socrates.num_teeth, socrates.IQ, socrates.sports_played,
socrates.knowledge[0].grammatical, socrates.knowledge[0].math
print socrates.knowledge
print socrates_Knowledge.grammatical, socrates_Knowledge.math,
socrates_Knowledge.human[0].sports_played
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Code from September 17, 2013 Lecture
class Person() :
name = None
parents = []
kids = []
has = None
def __init__(self, name) :
self.name = name
p1 = Person("phil")
p2 = Person("rita")
p3 = Person("chris")
p1.kids.append(p3)
p3.parents.append(p1)
print "My name is ", p1.name, "My first kids name is ", p1.kids[0].name
class Job():
name = ""
employees = []
def __init__(self, name) :
self.name = name
j1 = Job("professor")
j1.employees = []
# This was added after class.
p1.has = j1
j1.employees.append(p1)
print p1.has.name, j1.employees[0].name
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Code from September 17, 2013 Lecture
class Person(object):
_registry = [] # _registry starts off as an empty list.
name = ""
amount = 0
def __init__(self, name, amount):
self._registry.append(self) # Each instance of Person is added to _registry.
self.name = name
self.amount = amount
def exchange(self, p, amnt) :
self.amount -= amnt
p.amount += amnt
# Behavior or Method
p1, p2, p3, p4 = Person('tom', 1000), Person('jerry', 2000), Person('phineas', 3000), Person('ferb', 4000)
for p in Person._registry:
print p.name + ", " + str(p.amount) , # The comma at the end of the print statement causes all to print on one line.
def transfer(p1, p2, amnt) :
p1.amount -= amnt # Fill in these 2 lines for Homework 1. Note, the “transfer” function
p2.amount += amnt # requires no return statement.
transfer(p1, p2, 50)
transfer(p3, p4, 50)
print
for p in Person._registry:
print p.name + ", " + str(p.amount) ,
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# More on Next Page
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Code from September 17, 2013 Lecture
p1.exchange(p2, 50)
print
for p in Person._registry:
print p.name + ", " + str(p.amount) ,
p10 = Person("me", "you")
print
print p10._registry
print
print p1._registry
class MeekPerson(Person) :
def __init__(self, name, amount):
self._registry.append(self) # Each instance of Person is added to _registry.
self.name = name
self.amount = amount
def exchange(self, p, amnt) :
self.amount -= 2*amnt
p.amount += 2*amnt
m1 = MeekPerson("snoopy", 10000)
p6 = Person("charlie", 20000)
m1.exchange(p6,50)
print
for p in Person._registry:
print p.name + ", " + str(p.amount) ,
Dr. Philip Cannata
# Dynamic Binding will be done here to choose the right method.
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