Examples

Each item below is an example of the use of Silo to represent a different kind of scientific data. Each example shows a picture of the data (visualized with VisIt, describes some of the key concepts the example demonstrates, lists a set of key Silo functions the example uses and provides links to both C or C++ source code used to generate the data as well as the resulting Silo data file.

All of the examples here use some common Silo functions such as DBCreate and DBClose or functions to manage option lists such as DBMakeOptlist or DBAddOption. So, those functions are not explicitly mentioned.

Constructive Solid Geometry

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	csg.silo data file csg_mesh.C source code

• Key concepts: Representation of Constructive Solid Geometry (CSG) meshes, variables and materials defined on CSG meshes and multiple meshes in a single file, error controls.
• Silo functions: DBPutCSGZonelist, DBPutCsgmesh, DBPutCsgvar, DBPutMaterial, DBShowErrors.

Materials and Mixing Materials

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	specmix_quad.silo quadmesh file specmix_ucd.silo ucdmesh file specmix_quad.C source code

• Key concepts: Representation of the same mesh data on both quadrilateral (Quad) and unstructured (UCD) meshes, quadrilateral mesh with deformed (nonlinear) coordinates, representation of materials and mixing materials and material species.
• Silo functions: DBPutMaterial, DBPutMatspecies, DBPutQuadmesh, DBPutZonelist.

Parallel Decomposed Meshes

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	bigsil.silo data file bigsil.C source code pmpio_silo_test_mesh.c source code

• Key concepts: Representation of parallel decomposition of data using multi-block objects, grouping of blocks into groups using _visit_domain_groups convention and other conventions, use of directories within a silo file.
• Silo functions: DBMkDir, DBPutMaterial, DBPutMultimat, DBPutMultimesh, DBPutMultivar, DBPutQuadmesh, DBSetDir, DBWrite.

Also, be sure to read about the Multiple Independent File (MIF) parallel I/O paradigm. A pmpio.h header file is available to make MIF I/O easy.

Point (Gridless) Meshes

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	noise.silo data file noise.C source code

• Key concepts: Point (gridless) meshes and variables, use of directories, quadrilateral meshes and variables.
• Silo functions: DBMkDir, DBPutMaterial, DBPutPointmesh, [DBPutPointvar], DBPutQuadmesh, DBPutQuadvar, DBWrite.

Unstructured Zoo and Arbitrary Polyhedral Meshes

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	poly3d.silo data file testall.C source code

• Key concepts: Unstructured cell data (UCD) meshes with ordinary zoo type elements and arbitrary polyhedral elements.
• Silo functions: [DBFreeFacelist], DBPutFacelist, DBPutMaterial, DBPutMatspecies, DBPutQuadmesh, DBPutUcdmesh, DBPutUcdvar, DBPutZonelist, DBShowErrors, DBWrite, DBCalcExternalFacelist.

Block-Structured Adaptive Mesh Refinement Meshes

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	amr2d_mesh_config.xml config file amr2d_wmrgtree.silo data file amr3d_mesh_config.xml config file amr3d_wmrgtree.silo data file add_amr_mrgtree.C source file

• Key concepts: Adaptive Mesh Refinement (AMR) meshes, Quadmeshes, Mesh Region Grouping trees (Mrgtrees) and variables (Mrgvars), Grouping Element Maps (Groupelmaps). Without Mrgtrees, a multiblock mesh of Quadmeshes representing the different patches of an AMR hierarchy is not properly organized into an AMR hierarchy. The Silo file examples provided here contain two multi-block representations of the meshes, one without an Mrgtree and one with, so you can understand the difference and what the Mrgtree information is doing.
• Silo functions: DBMkMrgtree, DBAddRegion, DBAddRegionArray, DBPutMrgtree, DBPutGroupelmap, DBPutMrgvar.