1. Matthew Knepley
  2. PetscExtStokesSolvers


1)	You need to have installed PetscExt
2)	You need to specify the environment variable PETSCEXT_DIR
3)	To build executables, type 
		>make all

4)	To remove object and binary files, type
		>make clean_all

1)	Example launch scripts can be found in 
		>cd example-scripts/
	To use these scripts, you need to change the permissions. i.e;
		>cd example-scripts/
		>chmod a+x *.sh

2)	Example input files (in ascii) can be found in
		>cd input/
	The example problem defines a stiff, dense square inclusion embedded in a lower viscosity,density
	material. The square inclusion sinks under the external gravity force. The problem is discretised
	using Q1-P0 basis functions for velocity and pressure. The parameters used are:
		<background>	eta = 1,	rho = 1
		<inclusion>	eta = 10^6,	rho = 2
	The matrices were generated using an element resolution of 32 x 32.

		* Indicates that the input matrices and vectors are in ascii, matrix market format
		* Indicates the full path to the matrix file for each stokes operator
		* Indicates the full path a matrix file which is an approximation to S
		* Indicates the full path to right hand side vectors 
		* Indicates the type of Schur complement preconditioner. One of <none,uw,bfbt>

1)	( pc_BFBt.c, pc_BFBt.h ) is the original BFBt code from Uzawa algs.
	( _PC_bfbt.c _PC_bfbt.h ) is the newer version <untested>

2)	Some of the functionality in this driver routine should be moved into PetscExt.
	The ones I've ear marked for migration are:

	* timed_residual_hist.c
	* list_operations.c