Finite Element Discretization Library                                   __                       _ __ ___   / _|  ___  _ __ ___                      | '_ ` _ \ | |_  / _ \| '_ ` _ \                      | | | | | ||  _||  __/| | | | | |                      |_| |_| |_||_|   \___||_| |_| |_|http://mfem.orgMFEM is a modular parallel C++ library for finite element methods. Its goal isto enable the research and development of scalable finite element discretizationand solver algorithms through general finite element abstractions, accurate andflexible visualization, and tight integration with the hypre library.* For building instructions, see the file INSTALL, or type "make help".* Copyright and licensing information can be found in the file COPYRIGHT.* The best starting point for new users interested in MFEM's features is the  interactive documentation in examples/README.html.* Developers interested in contributing to the library, should read the  instructions and documentation in the CONTRIBUTING.md file.Conceptually, MFEM can be viewed as a finite element toolbox that provides thebuilding blocks for developing finite element algorithms in a manner similar tothat of MATLAB for linear algebra methods. In particular, MFEM provides supportfor arbitrary high-order H1-conforming, discontinuous (L2), H(div)-conforming,H(curl)-conforming and NURBS finite element spaces in 2D and 3D, as well as manybilinear, linear and nonlinear forms defined on them. It enables the quickprototyping of various finite element discretizations, including Galerkinmethods, mixed finite elements, Discontinuous Galerkin (DG), isogeometricanalysis, hybridization and Discontinuous Petrov-Galerkin (DPG) approaches.MFEM includes classes for dealing with a wide range of mesh types: triangular,quadrilateral, tetrahedral and hexahedral, as well as surface and topologicallyperiodical meshes. It has general support for mesh refinement, including localconforming and non-conforming (AMR) adaptive refinement. Arbitrary elementtransformations, allowing for high-order mesh elements with curved boundaries,are also supported.MFEM is commonly used as a "finite element to linear algebra translator", sinceit can take a problem described in terms of finite element-type objects, andproduce the corresponding linear algebra vectors and sparse matrices. In orderto facilitate this, MFEM uses compressed sparse row (CSR) sparse matrix storageand includes simple smoothers and Krylov solvers, such as PCG, MINRES and GMRES,as well as support for sequential sparse direct solvers from the SuiteSparselibrary. Nonlinear solvers (the Newton method), eigensolvers (LOBPCG), andseveral explicit and implicit Runge-Kutta time integrators are also available.MFEM supports MPI-based parallelism throughout the library, and can readily beused as a scalable unstructured finite element problem generator. MFEM-basedapplications require minimal changes to transition from a serial to ahigh-performing parallel version of the code, where they can take advantage ofthe integrated scalable linear solvers from the hypre library. Comprehensivesupport for other external packages, e.g. PETSc and SUNDIALS is also included,giving access to many additional linear and nonlinear solvers, preconditioners,time integrators, etc.For examples of using MFEM, see the examples/ and miniapps/ directories, as wellas the OpenGL visualization tool GLVis which is available athttp://glvis.org.This project is released under the LGPL v2.1 license with static linkingexception. See files COPYRIGHT and LICENSE file for full details.LLNL Release Number: LLNL-CODE-443211DOI: 10.11578/dc.20171025.1248