Examples#

Overview#

This section includes several suites of examples available in the examples directory. Each suite includes several “steps” which are examples that increase in complexity from one “step” to the next. In some cases, a later step may make use of output from an earlier step; these cases are clearly documented. Table 35 classifies the level of difficulty of each example suite and provides a general description of the type of problems discussed.

Table 35 Overview of example suites.#
Example Suite	Difficulty	Description
`box-2d`	novice	Simple axial and shear deformation in static and quasi-static simulations in 2D box with a mesh in an ASCII text file.
`box-3d`	novice	Same as `2d/box` but with a 3D box and a mesh from Gmsh or Cubit.
`strikeslip-2d`	beginner	Prescribed coseismic slip and multiple earthquake ruptures in 2D with a mesh from Gmsh or Cubit.
`reverse-2d`	beginner	Gravity, surface loads, and prescribed coseismic slip on multiple reverse faults in 2D with a mesh from Gmsh or Cubit.
`subduction-2d`	intermediate	Coseismic, postseismic, and creep deformation using a 2D subduction zone cross-section with a mesh from Gmsh or Cubit.
`subduction-3d`	intermediate	Close to research-complexity for a 3D subduction zone with a mesh from Cubit.
`magma-2d`	intermediate	Magma reservoir using poroelasticity.
`troubleshooting-2d`	novice	Troubleshooting errors in simulation in put files.

The subduction-3d example suite is the most advanced. Users wanting to use PyLith in their research should work through relevant beginner examples and then the subduction-3d examples.

Tip

You can use the pylith_cfgsearch utility (see Utilities) to search for examples based on keywords and features.

Prerequisites#

Before you begin any of the examples, you will need to install PyLith following the instructions in Installation. You should also read Running PyLith. Complete sets of input files are included in the examples. However, if you wish to generate the finite-element meshes yourself, you will also need Gmsh (available from https://gmsh.info and included in the PyLith binary package), Coreform Cubit (available from https://coreform.com/), or CUBIT (available to US federal government agencies from https://cubit.sandia.gov/). The ParaView https://www.paraview.org/ visualization package may be used to view simulation results. ParaView includes built-in documentation that is accessed by clicking on the Help menu item. Some additional documentation is available on the ParaView Wiki site https://www.paraview.org/Wiki/ParaView. You may use other visualization software, but some adaption from what is described here will be necessary.

Input Files#

The files needed to work through the examples are found in the examples directory under the top-level PyLith directory. All of the files used in the example problems are extensively documented with comments.

Visualizing PyLith Output#

See ParaView Python Scripts for a description of how to make use of the provided Python scripts for visualizing simulation output with ParaView. Alternatively, you can manually construct the visuzliation pipeline in several open-source visualization tools, such as ParaView and Visit.