-Constraint Domain Decomposition
We modified a few lines of the ESPResSo source code to obtain significant gains in simulation times (about 14x faster). In short, we added a simple domain decomposition algorithm for the particles of type constraints. Technical details can are shown in this presentation.
This was developped on ESPResSo version 2.1.2j to give it a try, you can downlaod our modiied source files and simply copy them over the ESPResSo 2.1.2j distribution. Please read the documentation for the usage details.
We hacked a bit at the external force (ext_force) module of EPREesSo to implement a 2D tabulated force (depending on the x,y coordnates of a bead). Our implementation reads a file called field.dat which contains four columns xpos, ypos, xforce, yforce on initialization and overrides these forces unto the ext_force value. The value numerical of ext_force is used to scale the tabulated forces. This hack only modifies the code contained in forces.c of ESPResSo version 2.1.2j.