Python Programming

This homework deals with the following topics:

1.Getting user input

2.Error checking

3.Variables & data types

4.Conditionals

General Idea of the Assignment

Lunar Lander is one of the earliest computer games. With a proper choice of initial values, it is fairly interesting to play, even though it is a text-only program.

You will take the role of an astronaut in the lunar module attempting to land on the moon's surface.

Gravity pulls you towards the moon at an increasing rate of speed. In order to land safely, you must burn fuel to counter gravity's acceleration to land on the moon at a safe speed (below 10 m/s). However, be careful, you can only use so much fuel. And if you are too high when you run out of fuel, you'll inevitably crash at an unsafe speed.

The Math

This game is not timed. Rather, you will \"simulate the passage of time by one second after each number entered. The game will play out as follows:

1. The player will be given their current altitude, velocity, and fuel.

2. The player will specify how much fuel to burn in the next second.

3. The game will perform the calculations of how the player's actions change altitude,

velocity, and fuel over the next \"second\".

4. If still above the moon's surface, go to step 1. Else, end the game (safely or otherwise ...)

These steps will be inside of a loop that runs while your altitude is positive. To create a while loop, you can use the following code in your program:

while altitude > 0:

#write your your code for the steps above #it will run indefinitely while altitude > 0

Note that it is unlikely you will hit zero altitude exactly. Instead, use altitude being less than or equal to zero as your termination condition.

Note that the game should set an initial altitude, velocity, and fuel amount. Altitude = 100.0 meters, velocity = 0.0 meters/second, and fuel = 100.0 liters can lead to interesting games.

To break down step 3, assume the following:

Each turn, your velocity increases by 1.6 meters per second due to the force of gravity of the moon (assume altitude doesn't affect the force generated by gravity).

Additionally, your velocity decreases by an amount proportional to the fuel you burn. This means you multiply fuel burnt times some constant to get the velocity change. Using a constant of 0.15 makes the game fairly easy to win. Note, a negative velocity means the lunar module is moving in reverse.

Your altitude decreases by your velocity (since you calculate every second, and your velocity is in meters per second, you don't have to do a multiplication step for units of time)

Your fuel decreases by the amount specified by the player.

Note that it is possible that a player tries to \"cheat by specifying an illegal amount of fuel to burn. We want to reasonably prevent these errors as follows:

If a player specifies burning zero fuel, this is fine (in fact, if they are out of fuel, this is their only choice).

If a player tries to burn a negative amount of fuel, treat it as if they burnt zero fuel. If a player specifies to burn more fuel than they have, burn all their fuel

If a player specifies an invalid amount i.e. a non-number) for fuel, print a friendly message and prompt the player to enter again.

The end game should specify:

Whether the landing was safe or not, (a safe landing is one where the final velocity is

10m/s)

At what velocity the landing occurred,

How many seconds the landing took, and

How much fuel is left.

Additionally, the program should ask if the player wants to play again. Any response that begins with Y' (capital or lowercase) should play again. Any response that begins with 'n' (capital or lowercase) means the user wants to exit. Any response that begins with any other character should ask the player again.

Submission

Your submission should include:

lunar_landing.py - the source code for your game This file must include a header, in the form of a multi-line comment at the top of your script, that contains (each on its own line):

- Your name

-Statement of work. Either:

A list of resources you used and/or people you received help from

(including TAs/Instructor)

A statement that you worked alone without help A comma-separated list of inputs that leads to a \"win\"

A comma-separated list of inputs that leads to a \"loss\"

Evaluation

Correctness - 10 pts

Does the game work as expected? Did you follow the directions exactly? Is your math correct? Does the comma-separated list of inputs that leads to a \"win\" allow the player to win the game? (Please note that we will not be running your code on any horrible inputs.)

Comments - 5 pts

Did you add clear and descriptive comments to all non trivial lines of code?