(sec-module-particles)= # Module: particles This module offers methods for GeneralContact, in particular particles (DEM - discrete element method) - **Author**: Johannes Gerstmayr - **Date**: 2024-10-19 (created) (sec-particles-createparticlesinbox)= ## Function: CreateParticlesInBox [`CreateParticlesInBox(minPointBox, maxPointBox, minRadius, maxRadius = None, maxNumberOfParticles = None, offsetRadius = 0, verbose = 0)`](https://github.com/jgerstmayr/EXUDYN/blob/master/python/exudyn/particles.py#L23) - **function description**: create set of spherical particles densly packed inside box using hexagonal closest packing (HCP); radius is randomized between minRadius and maxRadius - **input**: - `minPointBox`: [xMin,yMin,zMin] minimal cartesian coordinates for box - `maxPointBox`: [xMax,yMax,zMax] maximal cartesian coordinates for box - `minRadius`: minimal or nominal radius - `maxRadius`: maximal radius for randomized variations of radius or None to use minRadius - `maxNumberOfParticles`: if not None, this limits the amount of created particles; otherwise number of particles depends on geometry - `offsetRadius`: additional space between spheres (by assuming a larger radius for packing) - `verbose`: if > 0 some main parameters are printed - **output**: [(point0, radius0), ...] a list of point-radius tuples containing the information of created particles Relevant Examples (Ex) and TestModels (TM) with weblink to github: [`simulatorCouplingTwoMbs.py`](https://github.com/jgerstmayr/EXUDYN/blob/master/python/TestModels/simulatorCouplingTwoMbs.py) (TM)