MPE Theorie | Philip Brandt

Software and Numerics

Confusion of Classes?

This page contains useful drops of code. Well, actually I do not know if these lines are useful. Feel free to use these drops of code in your projects. But first...

Important notice:

This software is provided as-is, with all faults, without any express or implied warranty. In no event will the author(s) be held liable for any damages arising from the use of this software. Nevertheless I hope some of the code snippets provided here may be useful for someone.
For any information about errors or bugs, I am always grateful.

A CLR-Wrapper for the FFTW Library

FFTW is an optimized Fast-Fourier-Library for many platforms written in C by Matteo Frigo and Steven G. Johnson (see www.fftw.org). However, it is quite laborious to call this library via P/Invokes (for example using C#). This short snippet of code is a wrapper for the FFTW library with the following features:

The wrapper can be configured using XML-Files
By default the wrapper selects the right version of the FFTW library (x86 or x64 depending on your target system) at runtime.
Any specific low level calls are hidden.

Files

FFTW wrapper (complied, with sources) 2.2 MB
FFTW wrapper (just DLLs) 0.2 MB

A Tool for Visualization of Particle Data

Written in C++ and C#
Visualization of particle data via DirectX 11 Runtime and SlimDX, see http://archive.msdn.microsoft.com/D3D9ExDXGISharedSurf (MSDN-Code-Library) and http://windowsclient.net/blogs/rob_relyea/default.aspx ("WPF + Direct2D Sample") (Rob Relyea's Blog on WPF) for further details on implementation of surface sharing
Basic Tools for Pattern Analysis
- Filtering
- Local Bond Order (Steinhardt et al.)
- Legendre Bond Order (and local anisotropic order)
References ...
- Structural properties of dense hard sphere packings, B.A. Klumov, S.A. Khrapak, G. E. Morfill, arXiv:1101.5545v1 [cond-mat.soft] (2011)
- Accurate determination of crystal structures based on averaged local bond oder parameters, W. Lechner and C. Dellago, JCP 129, 114 707 (2008)
- Structural properties of complex plasmas in a homogeneous dc discharge, S. Mitic et al., PRL 101, 123002 (2008)
Import for CSV data and binary

Screenshot

Files

Tool 'View 3D Structures' (sources, complete Visual Studio 2010 Project)
Tool 'View 3D Structures' (just binaries, Windows x64, DirectX 11 Runtime, GPU with DirectX 10 feature level)
Tool 'View 3D Structures' (just binaries, Windows x86, DirectX 11 Runtime, GPU with DirectX 10 feature level)
Demo Data (CSV, Binary)

File formats

Binary Simulation Data (SimERMR):
Each file starts with a magic number, followed by the description of the particle set and the data of each particle:

Description	Size/Type	Comment
Magic Number	1 byte	0x79
Version	1 byte	0x02
Number of particles	4 bytes, int	N
Number of dimensions	4 bytes, int	dim
Size of each block	4 bytes, int
Boundary box	dim x 8 bytes, double
Particle positions	N x dim * 8 bytes, double	for each particle the coordinates are stored in ascending order, e.g. Particle1.x, Particle1.y, Particle1.z, Particle2.x,...
Particle data	N * 9 bytes, (byte, double)	for each particle a structure consisting of information about its species (byte) and description (double) is stored

CSV (F-Praktikum):
Each line of this text file contains the position of a particle (x,y,z). For a line the RegEx is given by
([-+]?[0-9]*\.?[0-9]+([eE][-+]?[0-9]+)?\s){3,}
and all other lines which are not matching this RegEx will be ignored.