# Latest Projects

## Simon’s famous times tables visualization poster

### The poster is 181,12 cm x 80,56 cm (height x width). Simon still has 2 copies available for 70 euros each, please buzz us if you are interested! The text at the bottom of the poster says:

This is a visualization for the times tables from 1 to 200.

Start with a circle with 200 points. Label the points from 0-199, then from 200-399, then from 400-599, and so on (you’re labeling the same point several times).

We’ll first do the 2× table. 2×1=2, so we connect 1 to 2. 2×2=4, so we connect 2 to 4, and so on. 2×100=200, where’s the 200? It goes in a circle, so 200 is where the 0 is, and now you can keep going. Now you could keep going beyond 199, but actually, you’re going to get the same lines you already had!

For the code in Processing, I mapped the two numbers I wanted to connect up (call them i), which are in between 0 and 200, to a range between 0 and 2π. That gave me a fixed radius (I used 75px) and an angle (θ). Then I converted those to x and y by multiplying the radius by cos(θ) for x, and the radius by sin(θ) for y. That gave me a coordinate for each point (and even in between points, so you can do the in between times tables as well!) Then I connect up those coordinates with a line. Now I just do this over and over again, until all the points are connected to something.

Idea: Times Tables, Mandelbrot and the Heart of Mathematics video by Mathologer (YouTube)

Code: by Simon Tiger (simontiger.com)

Download the animated version here: https://github.com/simon-tiger/times_tables

## Simon creates a playlist with Sorting Algorithms tutorials in Python

Simon has started a huge new project: a series of video tutorials about sorting algorithms. In the videos, he codes on his RaspberryPi, but here are the links to the Python code available on his GitHub page:

Parts 1 - 5: https://gist.github.com/simon-tiger/5be70247a066f69c2578be5bb8e41e59

Parts 6 - 7: https://gist.github.com/simon-tiger/be3864b36f6d89fecd06f150063a6321

Link to the project playlist on YouTube (that Simon continuously updates)

## Multiplicative Persistence in Wolfram Mathematica

Simon has tried Matt Parker’s multiplicative persistence challenge on Numberphile: by multiplying all the digits in a large number, looking for the number of steps it takes to bring that large number to a single digit. Are there numbers that require 12 steps (have the multiplicative persistence of 12)?

Simon has worked on this for two days, creating an interface in Wolfram Mathematica. He wrote the code to make the beautiful floral shapes above, they are actually graphs of how many steps three digit numbers take to get to single digit numbers (each ”flower” has the end result at its center).

See the video on YouTube