Related links for this tutorial could be found HERE
Start from printing “Hello World” is quite boring, it appears in almost every tutorial. Let’s do an interesting mini-project together. If you are a hard-core game player, it might be helpful for you while you are playing games.
Question
You are a game player controlling a hero to fight against monsters. According to the formulas in the game you playing, there are two variables that decide the damage you will made while fighting against monsters:
Damage = Attack * (100% + ExtraDamageMultiplier)
For example, if your attack is 1000, and yor EDM is 20%, the final damage you will made is 1000 * (100% + 20%) = 1200
Now we have two equipments but you can only pick one.
Eqip a:
Atk + 200
EDM + 10%
Eqip b:
Atk + 100
EDM + 20%
Your hero already have Atk and EDM, that means Atk and EDM may not start from 0.
Start From a Known Hero
Assume your hero already have:
Atk: 800
EDM: 5%
Python code to calculate the final DMG after equipping these two equipments is shown below:
use_eq_a = (800 + 200) * (1 + 0.05 + 0.1)
print('DMG after using a ' + str(use_eq_a))
use_eq_b = (800 + 100) * (1 + 0.05 + 0.2)
print('DMG after using b ' + str(use_eq_b))
Part 1. Learn to Calculate Damage After Wearing Equipments
The formula itself it exactly the same as what you need to type on a calculator.
You pass two results of using equp a and eqip b to two variables use_eq_a and use_eq_b and print them.
Things inside print() is what you want to see, python cannot put string - the description of the output(here is 'DMG after using a/b') and float - the calculating result together, so you need to convert float into string via str(). Things inside '' or "" defines a string directly, and + merges two string together.
Copy these code to your IDE and run it, there are multiple ways to run it in the VSCode
Put these code in a file called hero.py, select the lines you want to run and right-click, you will see a menu like this:
If you click the red part, vscode will pop out a terminal, and show the following message after running:
If you can see the blue part(Some body may not have it, it requires jupyter notebook, an external python plug-in and library), after clicking it, you will see:
The Third way need a VSCode plug in called Coderunner, you can install it in extension store by the steps shown on the following picture:
Than at the upper-right corner of your workspace, you can see a triangular buttom, click it to run the current file/selection
There is a strange output 1150.0000000000002, it is not an error, it caused by binary floating point in both C and Python(Python based on C), you can find the explaination HERE. But it doesn’t matter for the following comparison.
Part 2. Compare Two Results
Continue with the code above, now you already have 2 results and need to compare them, wear the equipment that allows you to kill monsters in the shortest time.
Add the if…elif…else after the code provided above
use_eq_a = (800 + 200) * (1 + 0.05 + 0.1)
print('DMG if use a ' + str(use_eq_a))
use_eq_b = (800 + 100) * (1 + 0.05 + 0.2)
print('DMG if use using b ' + str(use_eq_b))
if use_eq_a > use_eq_b:
print('choose a')
elif use_eq_a < use_eq_b:
print('choose b')
else:
print('two equipments are the same')
elif means else if(infact, many other languages use else if, but python use elif). The logit is exactly the same to the plain English. But, be careful with those spaces, I suggest you to use tab instead of pressing space multiple time for indent. Sentences on the same logic level need to have the same indent in python.
If you do
if sth:
execute thing 1
else:
execute thing 2
Python will throw out an error because I presses one more space before execute thing 2
After executing the code provided, what you will see in terminal will be like:
DMG if use a 1150.0000000000002
DMG if use using b 1125.0
choose a
