TRNG

# New TRNG release

A new version of TRNG (Tina’s Random Number Generator Library) has been released. TRNG may be utilized in sequential as well as in parallel Monte Carlo simulations. It does not depend on a specific parallelization technique, e.g., POSIX threads, MPI and others. The new version 4.15 is a bug fix and maintenance release. Classes for… Continue reading New TRNG release

# Eigenvalues and eigenfunctions

Computing the eigenvectors $\psi(x)$ and eigenvalues $E$ of some Hamiltonian $H$ belongs to the key problems of quantum mechanics. For the one-dimensional Schrödinger equation we have to solve $$E\psi(x) = H\psi(x) = -\frac{1}{2}\frac{\mathrm{d}^2\psi(x)}{\mathrm{d} x^2} + V(x)\psi(x)$$for some given potential $V(x)$. Analytical solutions, however, are scare goods. Thus, one has to rely on approximations… Continue reading Eigenvalues and eigenfunctions

Python

# Visualizing streamlines

In Visualizing vector fields I showed how to plot vector fields using Python and Matplotlib. Streamlines are a concept that is closely related to vector fields. Mathematically speaking streamlines are continuous lines whose tangent at each point is given by a vector field. Each line, and therefore also streamlines, can be parametrized by some parameter $t$.… Continue reading Visualizing streamlines

Python

# Visualizing vector fields

A vector field assigns to every point in space some vector. Vector fields are used in many branches of physics, e.g., to describe force fields, electromagnetic fields or velocity fields. Two-dimensional vector fields can be easily visualized using Python and the popular matplotlib package. As an example let us visualize the vector field \vec… Continue reading Visualizing vector fields

TRNG

# New TRNG release

A new version of TRNG (Tina’s Random Number Generator Library) has been released. TRNG may be utilized in sequential as well as in parallel Monte Carlo simulations. It does not depend on a specific parallelization technique, e.g., POSIX threads, MPI and others. The new version 4.14 is a bug fix and maintenance release introcucing compatibility… Continue reading New TRNG release

Python

# Point and interval estimation in Python

Let us consider a random sample $x_1,x_2,\dots,x_N$ drawn from a normal distribution with unknown mean $\mu$ and unknown variance $\sigma^2$. The best point estimates for the mean and the variance are given by the sample mean$$\hat\mu = \frac{1}{N}\sum_{i=1}^{N} x_i$$ and the sample variance $$\hat\sigma^2 = \frac{1}{N-1}\sum_{i=1}^{N} (x_i-\hat\mu)^2\,,$$ respectively. The sample mean… Continue reading Point and interval estimation in Python

# TRNG now on GitHub

As I pointed out earlier the open source software repository BerliOS will be closed at the end of this year. For this reason, Tina’s Random Number Generator Library is on GitHub now. You may checkout the whole version history starting from version 4.0 to the latest version 4.13 from the repository rabauke/trng4.

# BerliOS will be closed

Recently, the Fraunhofer Institute for Open Communication Systems announced to close BerliOS, its open source software repository, on 31.12.2011. BerliOS has been the home for Tina’s Random Number Generator Library (TRNG) for many years. Now, I have to find a new hosting platform for my little software project until the end of this year. Maybe,… Continue reading BerliOS will be closed

# New TRNG release

A new version of TRNG (Tina’s Random Number Generator Library) has been released. TRNG may be utilized in sequential as well as in parallel Monte Carlo simulations. It does not depend on a specific parallelization technique, e.g., POSIX threads, MPI and others. The new version 4.13 is a bug fix and maintenance release. If you… Continue reading New TRNG release

Software

# C++0x is unanimously approved

As Herb Sutter announced in his blog the ISO committee has approved a new C++ standard C++11. I  expect that compilers will adopt this standard timely.  Many  features of the new standard had been implemented long before it was approved.  C++11 will make modern C++ programming much more easy.