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diff toolbox/lotkin.m @ 2:c124219d7bfa draft

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Re-add the 1995 toolbox after noticing the statement in the ~higham/mctoolbox/ webpage.
author Antonio Pino Robles <data.script93@gmail.com>
date Thu, 07 May 2015 18:36:24 +0200
parents 8f23314345f4
children
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolbox/lotkin.m	Thu May 07 18:36:24 2015 +0200
@@ -0,0 +1,12 @@
+function A = lotkin(n)
+%LOTKIN  Lotkin matrix.
+%        A = LOTKIN(N) is the Hilbert matrix with its first row altered to
+%        all ones.  A is unsymmetric, ill-conditioned, and has many negative
+%        eigenvalues of small magnitude.
+%        The inverse has integer entries and is known explicitly.
+
+%        Reference:
+%        M. Lotkin, A set of test matrices, MTAC, 9 (1955), pp. 153-161.
+
+A = hilb(n);
+A(1,:) = ones(1,n);