octave:4> umfpack_simple
umfpack_simple is the file: /home/dbateman/octave/devel/octave-sparse/UMFPACKv4.3/UMFPACK/OCTAVE/umfpack_simple.m

umfpack_simple:  a simple demo of UMFPACK

UMFPACK Version 4.3 (Jan. 16, 2004), Copyright (c) 2004 by Timothy A.
Davis.  All Rights Reserved.

UMFPACK License:

    Your use or distribution of UMFPACK or any modified version of
    UMFPACK implies that you agree to this License.

    THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY
    EXPRESSED OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.

    Permission is hereby granted to use or copy this program, provided
    that the Copyright, this License, and the Availability of the original
    version is retained on all copies.  User documentation of any code that
    uses UMFPACK or any modified version of UMFPACK code must cite the
    Copyright, this License, the Availability note, and "Used by permission."
    Permission to modify the code and to distribute modified code is granted,
    provided the Copyright, this License, and the Availability note are
    retained, and a notice that the code was modified is included.  This
    software was developed with support from the National Science Foundation,
    and is provided to you free of charge.

Availability: http://www.cise.ufl.edu/research/sparse/umfpack

See also: umfpack, umfpack_details


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Hit enter to agree to the above License: 
A =

   2   3   0   0   0
   3   0   4   0   6
   0  -1  -3   2   0
   0   0   1   0   0
   0   4   2   0   1

b =

    8
   45
   -3
    3
   19

Solution to Ax=b via UMFPACK:
x1 = umfpack (A, '\', b)
x1 =

  1.00000
  2.00000
  3.00000
  4.00000
  5.00000

Solution to Ax=b via OCTAVE:
x2 = A\b
x2 =

  1.00000
  2.00000
  3.00000
  4.00000
  5.00000

norm (x1-x2) should be small: 0
Type 'umfpack_demo' for a full demo of UMFPACK
octave:5> diary off