A blog of Python-related topics and code.
A linear transformation in two dimensions can be visualized through its effect on the two orthonormal basis vectors and . In general, it can be represented by a matrix, , which acts on a vector to map it from a vector space spanned by one …
The mildly controversial geocoding system What3words encodes the geographic coordinates of a location (to a resolution of 3 m) on the Earth's surface into three dictionary words, through some proprietary algorithm. The idea is that humans find it easier to remember and communicate these words …
The magnetic field due to a magnetic dipole moment, at a point relative to it may be written where is the vacuum permeability. In geomagnetism, it is usual to write the radial and angular components of as: where is polar (colatitude) angle (relative to the …
The Earth Impact Database is a collection of images, publications and abstracts that provides information about confirmed impact structures for the scientific community. It is hosted at the Planetary and Space Science Centre (PASSC) of the University of New Brunswick. The code is also presented …
This code continues the previous blog post on two-dimensional collisions to model Brownian motion. The code is on my GitHub page. The core classes, PeriodicParticle and PeriodicSimulation are derived from the original Particle and Simulation classes to allow periodic boundary conditions: instead of bouncing off …
This small Python project is a physical simulation of two-dimensional physics. The animation is carried out using Matplotlib's FuncAnimation method and is implemented by the class Simulation. Each "particle" of the simulation is represented by an instance of the Particle class and depicted as a …
A previous blog post dealt with packing circles into a circle. To fill an arbitrary shape, a slightly different approach is needed. The code is presented in my github repo. A black-and-white PNG image should provided (the black areas to be filled). The ShapeFill class …
The following code attempts to pack a predefined number of smaller circles (of random radii between two given limits) into a larger one. The algorithm simply selects a random set of radii, sorts them into decreasing order (so the larger circles get placed first), and …
The Morse oscillator is a model for a vibrating diatomic molecule that improves on the simple harmonic oscillator model in that the vibrational levels converge with increasing energy and that at some finite energy the molecule dissociates. The potential energy varies with displacement of the …
The harmonic oscillator is often used as an approximate model for the behaviour of some quantum systems, for example the vibrations of a diatomic molecule. The Schrödinger equation for a particle of mass moving in one dimension in a potential is With the change of …
