Question

PYTHON

Exercise #2: Design and implement class Radio to represent a radio object. The class defines the following attributes (variables) and methods:

Assume that the station and volume settings range from 1 to 10.

1. A private variable of type int named station to represent a station number. Set to 1.

2. A private variable of type int named volume to represent the volume setting. Set to 1.

3. A private variable of type boolean named on to represent the radio on or off. Set to false.

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4. A non-argument constructor method to create a default radio.

5. Method getStation() that returns the station.

6. Method getVolume() that returns the volume.

7. Method turnOn() that turns the radio on.

8. Method turnOff() that turns the radio off.

9. Method stationUp() that increments the station by 1 only when the radio is on.

10. Method stationDown() that decrements the station by 1 only when the radio is on.

11. Method volumeUp() that increment the volume by 1 only when the radio is on.

12. Method volumeDown() that decrements the volume by 1 only when the radio is on.

13. Method toString()to printout a meaningful description of the radio as follows(if the radio is on):

The radio station is X and the volume level is Y. Where X and Y are the values of variables station and volume.

If the radio is off, the message is: The radio is off.

Now design and implement a test program to create a default radio object and test all class methods on the object in random order. Print the object after each method call and use meaningful label for each method call as shown in the following sample run.

Sample run:

Turn radio on:

The radio station is 1 and the volume level is 1.

Turn volume up by 3:

The radio station is 1 and the volume level is 4.

Move station up by 5:

The radio station is 6 and the volume level is 4.

Turn volume down by 1:

The radio station is 6 and the volume level is 3.

Move station up by 3:

The radio station is 9 and the volume level is 3.

Turn radio off.

The radio is off.

Turn volume up by 2:

The radio is off.

Turn station down by 2:

The radio is off.

PYTHON

Answer 1

Note: Please indent the code as per the provided screenshot of code. Otherwise, it raises indentation errors.

Program Screenshot:

#declare class Radio class Radio(): #Declare private variables by using underscore #before variable name #declare station variable and set to 1 station-1 #declare volume variable and set to 1 volume 1 #declare turned on variable and set to 1 turned on - False #A non argument constructor #which initialize all the values def init (self) self station- 1 self._volume 1 self. turned on False #implement method getStation() #to return the current station value def getstation (self): return self. station #implement method getvolume() #to return the current volume value def getVolume (self) return self. volume #Implement the method turnon() #that return true when it is on def turnon (self): self. turned on - True #Implement the method turnoff() #that return true when it is off def turnoff (self): self. turned on False #Implement the method stationUp #to return the value current station value def stationUp (self): if self. turned on: self station + 1 if self. station 10: self. station 10

#Implement the method stationDown #to return the value current station value def stationDown (self): if self. turned on: self. station -- 1 if self station< 1: self. station 1 #Implement the method VolumeUp #to return the value current volume value def volumeUp (self): if self. turned on: self. volume 1 if self volume > 10: self. volume = 10 #Implement the method volumeDown #to return the value current volume value def volumeDown (self) if self. turned on: self. volume -- 1 if self volume< 1: self. volume-1 #implement tostring() method to #print the station and volume values def toString (self): #lf radio is turned on if self. turned on: #print the values print ('The radio station is [0 and the volume level is (1. .format (self. station, self. volume)) #otherwise print the radio is off else: print ('The radio is off.')

#test program def main): #create an object for the radio class radio - Radio() #print the label for turn on the radio print ('Turn radio on:') radio.turnOn () #call the toString() method radio.toString () #call volumeUp methods to increase the volume radio.volumeUp () radio.volumeUp () radio.volumeUp () #print the label print ('Turn volume up by 3:') #call the tostring() method radio.toString () #call stationUp methods to increase the station radio.stationUp () radio.stationUp () radio.stationUp () radio.stationUp () radio.stationUp () #print the label print ('Move station up by 5:') #call the tostring() method radio.toString () #call volumeDown meth ds to decrease the volume radio.volumeDown () #print the label print ('Turn volume down by 1:) #call the tostring() method radio.toString ()

#call stationUp methods to increase the station radio.stationUp () radio.stationUp () radio.stationUp () #print the label print ("Move station up by 3:') #call the tostring() method radio.toString () #call method turnoff to turn off the radio radio.turnoff () #print the label for turn on the radio print('Turn radio off:') #call the tostring() method radio.toString () #call volumeUp methods to increase the volume radio.volumeUp () radio.volumeUp () #print the label print ('Turn volume up by 2:') #call the tostring() method radio.toString () #call stationDown method to decrease the station radio.stationDown () radio.stationDown () #print the label print('Turn station down by 2:') #call the tostring() method radio.toString () #main method main()

Sample Output:

Turn radio on: The radio station is 1 and the volume level is 1 Turn volume up by 3: The radio station is 1 and thevolume level is 4 Move station up by 5: The radio station is 6 and thevolume level is 4 Turn volume down by1: The radio station is 6 and the volume level is 3 Move station up by 3: The radio station is 9 and the volume level is 3 Turn radio off: The radio is off. Turn volume up by 2: The radio is off. Turn station down by 2: The radio is off.

Code to be Copied:

#declare class Radio

class Radio():

    #Declare private variables by using underscore

    #before variable name

    #declare station variable and set to 1

    _station=1

    #declare volume variable and set to 1

    _volume=1

    #declare turned_on variable and set to 1

    _turned_on = False

    #A non argument constructor

    #which initialize all the values

    def __init__(self):

        self.__station = 1

        self.__volume = 1

        self.__turned_on = False

    #implement method getStation()

    #to return the current station value

    def getStation(self):

        return self.__station

    #implement method getVolume()

    #to return the current Volume value

    def getVolume(self):

        return self.__volume

    #Implement the method turnOn()

    #that return true when it is on

    def turnOn(self):

        self.__turned_on = True

    #Implement the method turnOff()

    #that return true when it is off

    def turnOff(self):

        self.__turned_on = False

    #Implement the method stationUp

    #to return the value current station value

    def stationUp(self):

        if self.__turned_on:

            self.__station += 1

            if self.__station > 10:

                self.__station = 10

    #Implement the method stationDown

    #to return the value current station value

    def stationDown(self):

        if self.__turned_on:

            self.__station -= 1

            if self.__station < 1:

                self.__station = 1

    #Implement the method volumeUp

    #to return the value current volume value

    def volumeUp(self):

        if self.__turned_on:

            self.__volume += 1

            if self.__volume > 10:

                self.__volume = 10

    #Implement the method volumeDown

    #to return the value current volume value              

    def volumeDown(self):

        if self.__turned_on:

            self.__volume -= 1

            if self.__volume < 1:

                self.__volume = 1

    #implement toString() method to

    #print the station and volume values

    def toString(self):

        #if radio is turned on

        if self.__turned_on:

            #print the values

            print('The radio station is {0} and the volume level is {1}.'

                  .format(self.__station, self.__volume))

        #otherwise print the radio is off

        else:           

            print('The radio is off.')

#test program

def main():

    #create an object for the radio class

    radio = Radio()

    #print the label for turn on the radio

    print('Turn radio on:')

    radio.turnOn()

   

    #call the toString() method

    radio.toString()

    #call volumeUp methods to increase the volume

    radio.volumeUp()   

    radio.volumeUp()

    radio.volumeUp()

    #print the label

    print('Turn volume up by 3:')

    #call the toString() method

    radio.toString()

   

    #call stationUp methods to increase the station

    radio.stationUp()

    radio.stationUp()

    radio.stationUp()

    radio.stationUp()

    radio.stationUp()

    #print the label

    print('Move station up by 5:')

    #call the toString() method

    radio.toString()

    #call volumeDown methods to decrease the volume   

    radio.volumeDown()

    #print the label

    print('Turn volume down by 1:')

    #call the toString() method

    radio.toString()

    #call stationUp methods to increase the station

    radio.stationUp()

    radio.stationUp()

    radio.stationUp()

    #print the label

    print('Move station up by 3:')

  #call the toString() method

    radio.toString()

    #call method turnOff to turn off the radio

    radio.turnOff()

    #print the label for turn on the radio

    print('Turn radio off:')

    #call the toString() method

    radio.toString()

    #call volumeUp methods to increase the volume

    radio.volumeUp()

    radio.volumeUp()

    #print the label

    print('Turn volume up by 2:')

    #call the toString() method

    radio.toString()

   

    #call stationDown method to decrease the station

    radio.stationDown()

    radio.stationDown()

    #print the label

    print('Turn station down by 2:')

    #call the toString() method

    radio.toString()

   

#main method

main()