diff toolboxes/FullBNT-1.0.7/netlab3.3/rosegrad.m @ 0:e9a9cd732c1e tip

first hg version after svn
author wolffd
date Tue, 10 Feb 2015 15:05:51 +0000
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolboxes/FullBNT-1.0.7/netlab3.3/rosegrad.m	Tue Feb 10 15:05:51 2015 +0000
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+function g = rosegrad(x)
+%ROSEGRAD Calculate gradient of Rosenbrock's function.
+%
+%	Description
+%	G = ROSEGRAD(X) computes the gradient of Rosenbrock's function at
+%	each row of X, which should have two columns.
+%
+%	See also
+%	DEMOPT1, ROSEN
+%
+
+%	Copyright (c) Ian T Nabney (1996-2001)
+
+% Return gradient of Rosenbrock's test function
+
+nrows = size(x, 1);
+g = zeros(nrows,2);
+
+g(:,1) = -400 * (x(:,2) - x(:,1).^2) * x(:,1) - 2 * (1 - x(:,1));
+g(:,2) = 200 * (x(:,2) - x(:,1).^2);