Out: Thursday, July 11, 2002
Due: Thursday, July 18, 2002 before midnight
The Objective
This project will give you practice using arrays and passing
arrays to functions. You will be able to modify your code from
Project 3.
The Background (Same as Project #3)
Mathematicians and other scientists find unexpected applications for
power series approximation. In 1772, the astronomer J. E. Bode proposed
a rule for calculating the distance from the sun to each of the planets
known at that time. To apply that rule, which subsequently became known
as Bode's law, you begin by using the sequence:
b1 = 1, b2 = 3, b3 = 6,
b4 = 12, b5 = 24, b6 = 48
where each subsequent element in the sequence is twice the preceding
one. It turns out that an approximate distance to the ith planet can be
computed from this series by applying the formula
d i = ( 4 + b i ) / 10
The distance is given in astronomical units; an astronomical unit
(AU) is the average distance from the sun to the earth, which is approximately
93,000,000 miles. Except for a disconcerting gap between Mars and Jupiter,
Bode's law gives reasonable approximations for the distances to the seven
planets that were known in Bode's day:
Distance from the Sun
Mercury 0.5 AU 4.650000e+07 miles
Venus 0.7 AU 6.510000e+07 miles
Earth 1.0 AU 9.300000e+07 miles
Mars 1.6 AU 1.488000e+08 miles
? 2.8 AU 2.604000e+08 miles
Jupiter 5.2 AU 4.836000e+08 miles
Saturn 10.0 AU 9.300000e+08 miles
Uranus 19.6 AU 1.822800e+09 miles
Concern about the gap in the sequence led astronomers to discover the
asteroid belt, which they decided was left over after the destruction of
a planet that had once orbited the sun at the distance specified by the
missing entry in Bode's table.
The Task
You are to expand on the program you wrote for Project 3
. Instead of calculating each distance and printing out a table
of all the planets, you are going to store all of the values in arrays.
You will need two arrays,
one to store the AU values and one to store the miles values. You will
display a menu to the user. The user can then
select which planet's information he/she would like to see.
You'll be expected to write a minimum of seven functions, other than
main, for this project.
Here are the function prototypes:
void PrintExplanation (void);
void PrintMenu (void);
int GetValidChoice(void);
int GetTermValue (int index);
void FillAUArray (double au[], int size);
void FillMilesArray(double miles[], double au[], int size);
void PrintPlanetInfo (int choice, double au[], double miles[]);
Function Descriptions:
PrintExplanation - should print a message to the user, explaining what
the program will do. Since this function returns nothing, it can also be
called a procedure.
PrintMenu - This function prints a menu to user which lists
the planets. See sample output.
GetValidChoice - This function gets a number from the user that
is between 1 and 8 inclusive. This number is the user's menu
choice.
GetTermValue - This function will take an integer (the index of the term)
as its single argument, index, and return the value of that term in the
sequence. The values of the first two terms in the series are 1 and 3,
respectively. The values of all of the other terms are to be calculated
based on the index of the term. DO NOT HARD CODE THE TERM VALUES
for the terms of index > 2.
FillAUArray - This function fills an array with the AU values for
all 8 planets
FillMilesArray - This function fills an array with the miles
values for all 8 planets.
PrintPlanetInfo - This function prints out information about
one planet. choice determines which planet is printed.
Sample Output
[Your explanation to the user goes here].
1) Mercury
2) Venus
3) Earth
4) Mars
5) Asteroid Belt
6) Jupiter
7) Saturn
8) Uranus
9) Quit
Which planet's information would you like to see? 1
Mercury is the closest planet to the Sun.
It is 0.5 astronomical units, which is 4.650000e+07 miles, from the Sun.
1) Mercury
2) Venus
3) Earth
4) Mars
5) Asteroid Belt
6) Jupiter
7) Saturn
8) Uranus
9) Quit
Which planet's information would you like to see? 2
Venus is the second planet from the Sun.
It is 0.7 astronomical units, which is 6.510000e+07 miles, from the Sun.
1) Mercury
2) Venus
3) Earth
4) Mars
5) Asteroid Belt
6) Jupiter
7) Saturn
8) Uranus
9) Quit
Which planet's information would you like to see? 3
Earth is the third planet from the Sun.
It is 1.0 astronomical units, which is 9.300000e+07 miles, from the Sun.
1) Mercury
2) Venus
3) Earth
4) Mars
5) Asteroid Belt
6) Jupiter
7) Saturn
8) Uranus
9) Quit
Which planet's information would you like to see? 4
Mars is the fourth planet from the Sun.
It is 1.6 astronomical units, which is 1.488000e+08 miles, from the Sun.
1) Mercury
2) Venus
3) Earth
4) Mars
5) Asteroid Belt
6) Jupiter
7) Saturn
8) Uranus
9) Quit
Which planet's information would you like to see? 5
There is a gap in between Mars and Jupiter. It was discovered to be an asteroid belt.
It is 2.8 astronomical units, which is 2.604000e+08 miles, from the Sun.
1) Mercury
2) Venus
3) Earth
4) Mars
5) Asteroid Belt
6) Jupiter
7) Saturn
8) Uranus
9) Quit
Which planet's information would you like to see? 9
Thank you for using this program!
Submitting the Program
To submit the file you should use the command:
submit cs104 Proj4 proj4.c
You can check your submission by using the command: