1: Overview of Data Structures and Algorithms

Example 1: Page 20

In [1]:
class Thermostat:
	"""A simple thermostat class"""
	#since private instance variables don't exist in Python,
	#hence using a convention: name prefixed with an underscore, to treat them as non-public part
	def __init__(self):
		self._currentTemp = 0.0
		self._desiredTemp = 0.0

	def furnace_on(self):
		#method body goes here
		pass

	def furnace_off(self):
		#method body goes here
		pass
#end class Thermostat

Example 2: Page 22

In [2]:
#demonstrates basic OOP syntax

class BankAccount:
	"""A simple bank account class"""
	
	def __init__(self, openingBalance):	#special method to create objects
	#with instances customized to a specific initial state
		
		#since private instance variables don't exist in Python,
		#hence using a convention: name prefixed with an underscore, to treat them as non-public part
	    self._balance = openingBalance	#account balance

	def deposit(self, amount):	#makes deposit
		self._balance = self._balance + amount

	def withdraw(self, amount):	#makes withdrawl
		self._balance = self._balance - amount

	def display(self):	#displays balance
		print 'Balance=', self._balance
#end class BankAccount

ba1 = BankAccount(100.00)	#create account

print 'Before transactions, ',
ba1.display()	#display balance

ba1.deposit(74.35)	#make deposit
ba1.withdraw(20.00)	#make withdrawl

print 'After transactions, ',
ba1.display()	#display balance
#end
Before transactions,  Balance= 100.0
After transactions,  Balance= 154.35

Example 3: Page 25

In [3]:
#creating string objects
str1 = ''
str2 = 'George'

#verifying results
print str1
print str2

#naming string object
str3 = 'amanuensis'

#verifying results
print str3

#accessing specific characters from string using [] operator
ch1 = str2[3]

#verifying results
print ch1

#finding and printing number of characters in a string
print len(str1)
George
amanuensis
r
0