## Chapter 7 Code Examples

### MATLAB Code Examples

format bank bill=input('Enter the amount of the bill (in dollars): '); if (bill <= 10) tip = 1.8; elseif (bill > 10) & (bill <= 60) tip = bill*0.18; else tip = bill*0.2; end disp('The tip is (in dollars):') disp(tip)

n = 1; while (n ~= 0) x = input (‘Resistance: ‘); switch x case 100 disp (x) case 200 disp (x) case 300 disp (x) case 400 disp (x) otherwise n = 0; end end

### Python Code Examples

bill=int(input('Enter the amount of the bill (in dollars): ')) if (bill <= 10): tip=1.8 elif (bill>10)and(bill<=60): tip=bill*0.18 else: tip=bill*0.2 print('The tip is (in dollars): %0.2f'% (tip))

## Exercises

- Expanding on problem 1 from chapter 6, implement your algorithm. The problem description is restated below.

Write a script called “quadroots” to solve the real roots of a quadratic equation:

Your algorithm should ask the user for the coefficients. To calculate the roots of the equation, your algorithm should calculate the discriminant D given by:

If D > 0, the algorithm displays a message: “The equation has two roots” and then displays the roots.

If D = 0, the algorithm displays a message: “The equation has one root”, and then displays the root.

If D < 0, the algorithm displays a message: “The equation has no real roots”. - Expanding on problem 2 from chapter 6, implement your algorithm. The problem description is restated below.

Write a program that calculates the cost of a car rental according to the following price schedule:

Type of Car | Rental Period | ||

1-6 Days | 7-27 Days | 28-60 Days | |

Class B | $27 per day | $162 for 7 days, +$25 for each additional day | $662 for 28 days, +$23 for each additional day |

Class C | $34 per day | $204 for 7 days, +$31 for each additional day | $810 for 28 days, +$28 for each additional day |

Class D | Class D cannot be rented for less than 7 days | $276 for 7 days, +$43 for each additional day | $1,136 for 28 days, +$38 for each additional day |

The program asks the user to enter the rental period and type of car. The program then displays the appropriate cost. If a period longer than 60 days is entered, a message “Rental is not available for more than 60 days” is displayed. If a rental period of less than 6 days is entered for Class D, a message “Class D cars cannot be rented for less than 6 days” is displayed.