Viewing posts by christian
The Lorenz attractor
Posted by: christian on 4 Dec 2015
The Lorenz system of coupled, ordinary, first-order differential equations have chaotic solutions for certain parameter values $\sigma$, $\rho$ and $\beta$ and initial conditions, $u(0)$, $v(0)$ and $w(0)$.
House buyers avoid completing on the 13th of the month
Posted by: christian on 3 Dec 2015
Using the database of the UK land registry's record of house sales, we can extract the total number of sales for each day as follows:
The moment of inertia of a random flight polymer
Posted by: christian on 4 Nov 2015
A simple model of a polymer in solution treats its monomer units as totally uncorrelated in position (each monomer unit adopts a random orientation with respect to all the others): this is the random flight model.
Making a Matplotlib plot look better #1
Posted by: christian on 19 Oct 2015
Before Everest was climbed, the "World summit record" was the highest mountain summit climbed by a particular date. It seems likely that people in South America reached several peaks well in excess of 6000 m before records began, so the following table (adapted from Wikipedia's World altitude record article starts only with the first recorded ascent of Aconcagua in 1897.
Counting seeds with Python
Posted by: christian on 21 Sep 2015
On Sunday my daughter and I planted some cress seeds. The packet claimed that it contained an average of 500 seeds, so here's an attempt to validate that claim using Python. We planted the seeds on kitchen towel, so there is a good contrast between the seeds and the background (click for the full size image).