[cig-commits] r7226 - short/3D/PyLith/trunk/doc/userguide/intro

[knepley at geodynamics.org]

Author: knepley
Date: 2007-06-14 07:17:55 -0700 (Thu, 14 Jun 2007)
New Revision: 7226

Modified:
   short/3D/PyLith/trunk/doc/userguide/intro/intro.lyx
Log:
Some work on the manual


Modified: short/3D/PyLith/trunk/doc/userguide/intro/intro.lyx
===================================================================
--- short/3D/PyLith/trunk/doc/userguide/intro/intro.lyx	2007-06-14 13:50:50 UTC (rev 7225)
+++ short/3D/PyLith/trunk/doc/userguide/intro/intro.lyx	2007-06-14 14:17:55 UTC (rev 7226)
@@ -161,13 +161,13 @@
  equations.
  PETSc includes solvers that implement a variety of Newton and Krylov subspace
  methods.
- It can also interface with many external packages, including BlockSolve95,
- ESSL, Matlab, ParMeTis, PVODE, and SPAI, thereby providing additional solvers
+ It can also interface with many external packages, including ESSL, MUMPS,
+ Matlab, ParMeTis, PVODE, and Hypre, thereby providing additional solvers
  and interaction with other software packages.
 \end_layout
 
 \begin_layout Standard
-PETSc includes interfaces for Fortran, C, and C++ for nearly all of the
+PETSc includes interfaces for Fortran 77/90, C, C++, and Python for nearly all of the
  routines, and PETSc can be installed on most Unix systems.
  PETSc can be built with user-supplied, highly optimized linear algebra
  routines (e.g., ATLAS and commercial versions of BLAS/LAPACK), thereby improving
@@ -321,30 +321,50 @@
  Active development of purely analytic features in PyLith, such as new material
  models or discretization schemes, depends on the familiarity of application
  scientists with the traditional Fortran programming paradigm.
- Global, topological operation should be strictly segregated from the existing
+ Global, topological operations such as parallel assembly were strictly segregated from the preexisting
  code.
- In fact, with the exception of integrating PETSc for serial linear algebra
- and solver operations, PyLith can be run purely in serial without activating
+ In fact, PyLith can be run purely in serial without activating
  any of the parallel capabilities.
 \end_layout
 
 \begin_layout Standard
-In order to accomplish this separation, we use the PETSc 
+In order to accomplish this separation in version 0.8, we use the PETSc 
 \family typewriter
 Sieve
 \family default
  structure to create a model of the serial PyLith mesh.
  This model is then partitioned and distributed to a set of processes.
- Each process receives a self-consistent mesh, meaning the pieces are overlappin
-g.
- Each process then executes a serial PyLith step on that particular mesh
+ Each process receives a self-consistent mesh, meaning the pieces are overlapping,
+ and then executes a serial PyLith step on that particular mesh
  piece.
- The PETSc linear algebra operations are overloaded, using the 
+ The PETSc assembles these pieces, using the 
 \family typewriter
 Sieve
 \family default
- information, to produce a globally consistent field.
+ information, into globally consistent vectors and matrices.
 \end_layout
 
+\begin_layout Standard
+Our new design begins with the
+\family typewriter
+Sieve
+\family default
+to represent the topology of our domain. Zero volume elements are inserted along
+all fault surfaces which can implement both split node and cohesive element schemes.
+Material properties and other parameters are represented as
+\family typewriter
+Sections
+\family default
+over the sieve, and values can be retrieved by restriction. For each problem, methods
+are provided to calculate the residual and its Jacobian. All analytic work is done in
+these functions, and parallel assembly is accomplished using the restrict/update paradigm
+from the
+\family typewriter
+Sieve
+\family default
+framework. We assemble into PETSc linear algebra objects and then call PETSc solvers. The solution
+is mapped back into a section, which can be output in VTK format.
+\end_layout
+
 \end_body
 \end_document