Draco

Draco is an object-oriented component library geared towards numerically intensive, radiation (particle) transport applications built for parallel computing hardware. It consists of semi-independent packages and a robust build system. The packages in draco provide a set of components that can be used by multiple clients to build transport codes. The build system can also be extracted for use in clients.

To clone draco:

$ git clone https://github.com/lanl/Draco.git

To get started, please see Development - Quick Start Guide in the wiki. Pull requestes must satisfy the requirements listed in the Style Guide.

Synopsis of Active Draco Packages

• c4 - A communications library for message passing interfaces (MPI).
  • For builds without MPI, all communication commnds will be no-op functions (DRACO_C4={MPI;SCALAR}).
• cdi - Access to material data. The Common Data Interface (CDI) specifies a common abstraction for objects and libraries that return material data (opacities, atomic cross sections, equation-of-state data, etc.)
• cdi_analytic - Analytic models for physical data
• cdi_eospac - Equation-of-State data
  • These classes wrap the EOSPAC6 libraries that read sesame files; Commonly used to access gray opacity data and heat capacities. (EOSPAC_LIB_DIR=<path>).
• cdi_ipcress - Gray and multigroup opacities
  • The classes in this component will read and parse opacity values from an IPCRESS file produced by TOPS.
• compton - Provides access to Compton scattering models and data as provided by the CSK library.
• device - Wrapper for heterogeneous device communication
  • The classes in this component provide access to DaCS (deprecated) and CUDA calls for use on heterogeneous architecture platforms (GPU machines).
• diagnostics - CPP macros that are activated at compile time that can provide additional diagnostic verbosity during calculations.
• ds++ - Basic services and data structures library.
  • Array containers, assertion and Design-by-Contract, access to low level OS functions, file and path manipulation, unit test system, etc.
• fit - Least squares fitting routines.
• fpe_trap - Catch IEEE floating point exceptions
• FortranCheck - Test Fortran compatibility and interoperability
  • The examples in this component will demonstrate if the Fortran compiler is working; if Fortran/C interlanguage linking/running is working and sample ISO_C_BINDING calls.
• lapack_wrap - C++ wrapper for BLAS and LAPACK.
• linear - direct solvers for small linear systems of equations.
• mesh - Encapsulate mesh definition and accessors.
• mesh_element - defines fundamental mesh element types used by mesh, meshReaders and RTT_Format_Reader.
• meshReaders - Read RTT format mesh files.
• min - Optimization routines. Find the minimum of a function.
• norms - Calculate norms for data sets.
• ode - Ordinary differential equation solvers (e.g.: Runge-Kutta).
• parser - Lexical file/input parser.
• plot2d - C++ interface to XMGrace 2-dimensional plotting.
• quadrature - access to angular integration functions and related data.
• rng - A random number generator component
  • The primary set of functions provided by this component were derived from Random123 (https://www.deshawresearch.com/downloads/download_random123.cgi) random number library. A few additional random number generators are also provided.
• roots - Root finding algorithms
• RTT_Format_Reader - meshReaders implementation for RTT format mesh files or input-streams.
• shared_lib - Dynamically load/unload shared object libraries via dl load
• special_functions - Specialized math functions like factorial and Dirac delta.
• timestep - An object-oriented class that encapsulates a time step controller.
• traits - A traits class used by viz.
• units - Provides encapsulated unit systems, functions to convert between unit systems and physical constants.
• VendorChecks - A testing component to ensure that discovered and used vendor libraries behave as expected.
• viz - Generates Ensight files for data visualization.

Authors

Many thanks go to Draco's contributors.

Draco was originally written by staff from Los Alamos's CCS-2 Computational Physics and Methods Group:

CCS-2 Draco Team: Kelly G. Thompson, Kent G. Budge, Ryan T. Wollaeger, James S. Warsa, Alex R. Long, Kendra P. Long, Jae H. Chang, Matt A. Cleveland, Andrew T. Till, and Tim Kelley.

Prior Contributers: Gabriel M. Rockefeller, Allan B. Wollaber, Lori A. Pritchett-Sheats, Rob B. Lowrie, Paul W. Talbot, Katherine J. Wang, Peter Ahrens, Daniel Holladay, Jeff D. Densmore, Massimiliano Rosa, Todd J. Urbatsch, Jeff Furnish, John McGhee, Kris C. Garrett, Mike Buksas, Nick Myers, Paul Henning, Randy Roberts, Seth Johnson, Todd Adams, and Tom Evans.

Release

Draco is released under the BSD 3-Clause License. For more details see the LICENSE file.