Question

code. 23.16 Write an RGB class that represents an RGB color. Store the red, green. and blue components. Include a _str_0 method and a luminance method that returns the luminance of the color. Write a main() function to test your code. 23.17 Write a CD class that represents a single music cd. Store the artist, title, genre, year of release, and playing time in minutes and seconds. However, instead of providing all of these as parameters to __init_(), write your class so that only the artist and title are passed to the constructor. Set! the other fields to None initially, but provide setyear(), setgenre(), and setplayingtime() methods so that they can be set later. Have the str_0 method return the artist, title, and year, but only include the year if it was previously set. Write a main() function to test your code. 23.18 Write a Card class that ronno

please help with the marked ones the programming language is python

Answer 1

For 23.16

Here i used luminance formula as

luminance = (r * 0.3) + (g * 0.59) + (b * 0.11) where r = red ; g = green; b = blue;

Code:

class RGB: def __init__(self,red,green,blue): self.red = red self.green = green self.blue = blue    def __str__(self): return ("red = " + str(self.red)+ ", green = " + str(self.green)+ ", blue = " +str(self.blue))    def luminance(self): lumi = (self.red * 0.3) + (self.green * 0.59) + (self.blue * 0.11) return(lumi)    def main(): red = 100 green = 200 blue = 150    RGBColour = RGB(red,green,blue)    print(RGBColour) print(RGBColour.luminance())    main()

For 23.17

Code:

class CD: def __init__(self,artist,title): self.artist = artist self.title = title self.genre = None self.yearOfRelease = None self.playingTime = None    def setyear(self,year): self.yearOfRelease = year    def setgenre(self,genre): self.genre = genre    def setplayingtime(self,minutes,seconds): self.playingTime = minutes*60 + seconds    def __str__(self): if(self.yearOfRelease): return ("artist = " + str(self.artist) + ", title = " + str(self.title) + ", year = " + str(self.yearOfRelease)) else: return("artist = " + str(self.artist) + ", title = " + str(self.title))    def main(): #if year of yearOfRelease was previously set cd1 = CD("Patricio Sardelli","Airbag") cd1.setyear(1999) cd1.setgenre("Hard rock") cd1.setplayingtime(2,30)    print(cd1) #if year of yearOfRelease was not previously set cd2 = CD("Guido Sardelli ","Voragine ") cd2.setgenre("Progressive rock") cd2.setplayingtime(1,30)    print(cd2) main()