## Calculating distance with Python

I am very keen to help people **connections between Maths and Computer Science**. Above is a game I wrote using JavaScript. When you click on an “x” you have a 50% chance of being told the distance from the treasure.

Distance between points on a 2D plane is something we calculate using **Pythagoras’ Theorem**. If you need a reminder, maybe check out mathsisfun or the image below for a condensed version.

We are going to Write a Python program to compute the distance between the points (x1, y1) and (x2, y2). You are going to need to be a little bit flexible with your reasoning about variables here. In the code, `p1`

is point 1, which corresponds to `(x1, y1)`

, and similarly, `p2`

corresponds to `(x2, y2)`

.

We can do this with or without a **function.**

Lets look at the most simple way first:

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import math p1 = [4, 0] p2 = [6, 6] distance = math.sqrt(((p1[0] - p2[0]) ** 2) + ((p1[1] - p2[1]) ** 2)) print(distance) |

Notes: – **Don’t just copy-paste**. You should study the code, then try and reproduce it yourself. If you get stuck, then copy by typing, not pasting. You will learn much more this way, I promise. – We’ve used lists instead of tuples to keep things simple – if that makes no sense, don’t worry.

Depending on your experience level, you may be able to put the distance-calculating code into a handy re-usable function. Try this as an exercise for yourself if you like. **Hint: what would the parameters be?**

So there you have it – how to calculate the distance between two points with Python, and a fun game to play too.