File: README
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	CORE Library: $Id: README,v 1.1.1.1 2002/02/28 07:55:45 exact Exp $
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These programs implement the straightforward Gaussian elimination
algorithm, without pivoting.  The main point of the example is
to illustrate the difference between running these programs
in level 3 and level 1.

To test the programs, type

	% make all		// compiles "gaussian.cc" at levels 1 and 3
	% make test		// runs the programs on input matrices
				//	MatZero4, MatHilbert6

Results:
	MatHilbert6 is the 6x6 Hilbert matrix.
	The determinant of a nxn Hilbert matrix is Theta of 2^{-2n^2}.
	In level 1, the answer is NaN (probably underflow).
	
	MatZero4 is a 4x4 matrix whose determinant is 0.
	In level 1, the answer is 2.9976e-15.

DESCRIPTION OF FILES:

gaussian.cc:
	uses simple (non-pivoting)
	Gaussian elimination to compute the determinant.

gaussianX.cc:
	a version which has the input matrix hardcoded.

inputs:
	subdirectory with sample matrices
	See the README file there for more details


