ahbarnett / nodaldomains

extract nodal domains, their genus and percolation properties, from 2D or 3D gridded functions

nodaldomains

extract nodal domains, their genus and percolation properties, from 2D or 3D uniformly gridded functions. C++ code with MATLAB/octave wrappers.

Main author: Alex Barnett (c) 2017

Code contributions/acknowledgments: Kyle Konrad (2011-2012), Matthew Jin (2014-2015), Ziff-Newman, Tarjan, Sedgewick percolation algorithms (2001).

Dependencies

• C++ compiler and GNU make
• If you want interfaces to them: MATLAB and/or octave (including its development libraries)

Installation

From the main directory:

make test compiles the library domainlib.o then tests it via C++ drivers.

make octave builds and tests the octave interfaces.

make matlab builds the MATLAB interface; use test_nodal3dziff.m and test_perc3d.m to test.

Run make to see other options.

Codes

The following routines are available in the library, and MATLAB/octave functions:

• nodal2dziff and nodal3dziff : returns labeled nodal domains, and list of their sizes, for a real function given on 2D or 3D cubical grid, using quick union/find.

• perc2d and perc3d : estimates percolation threshold h0 for real function given on 2D or 3D cubical grid, and nodal domain information at threshold, using quick union/find in style of Newman-Ziff.

• genus3djin (MATLAB/octave only) : extracts genus and neighbor relations from labeled nodal domains on a 3D cubical grid.