A blog of Python-related topics and code.
Visualizing the Earth's dipolar magnetic field
Posted by: christian in Featured on frontpage on 28 Aug 2019
The magnetic field due to a magnetic dipole moment, $\boldsymbol{m}$ at a point $\boldsymbol{r}$ relative to it may be written $$ \boldsymbol{B}(\boldsymbol{r}) = \frac{\mu_0}{4\pi r^3}[3\boldsymbol{\hat{r}(\boldsymbol{\hat{r}} \cdot \boldsymbol{m}) - \boldsymbol{m}}], $$ where $\mu_0$ is the vacuum permeability. In geomagnetism, it is usual to write the radial and angular components of $\boldsymbol{B}$ as: $$ \begin{align*} B_r & = -2B_0\left(\frac{R_\mathrm{E}}{r}\right)^3\cos\theta, \\ B_\theta & = -B_0\left(\frac{R_\mathrm{E}}{r}\right)^3\sin\theta, \\ B_\phi &= 0, \end{align*} $$ where $\theta$ is polar (colatitude) angle (relative to the magnetic North pole), $\phi$ is the azimuthal angle (longitude), and $R_\mathrm{E}$ is the Earth's radius, about 6370 km. See below for a derivation of these formulae.
Some analysis of the demographics of India
Posted by: christian on 2 Aug 2019
This Jupyter Notebook can be downloaded and viewed at my GitHub repository.
Impact craters on Earth
Posted by: christian in Featured on frontpage on 28 Jul 2019
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 Star Wars opening crawl in Matplotlib
Posted by: christian on 21 Jul 2019
Matplotlib isn't the obvious choice for depicting the Star Wars opening crawl, but that isn't a reason not to try:
A simple two-dimensional Brownian motion animation
Posted by: christian on 3 Jul 2019
This code continues the previous blog post on two-dimensional collisions to model Brownian motion. The code is on my GitHub page.