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<a name="Numerical-Hessian-function"></a>
<h3 class="section">4.4 Numerical Hessian function</h3>
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<a name="Helptext_003a-13"></a>
<h4 class="subheading">Helptext:</h4>
<a name="XREFnumhessian"></a><pre class="verbatim">numhessian(f, {args}, minarg)
Numeric second derivative of f with respect
to argument "minarg".
* first argument: function name (string)
* second argument: all arguments of the function (cell array)
* third argument: (optional) the argument to differentiate w.r.t.
(scalar, default=1)
If the argument
is a k-vector, the Hessian will be a kxk matrix
function a = f(x, y)
a = x'*x + log(y);
endfunction
numhessian("f", {ones(2,1), 1})
ans =
2.0000e+00 -7.4507e-09
-7.4507e-09 2.0000e+00
Now, w.r.t. second argument:
numhessian("f", {ones(2,1), 1}, 2)
ans = -1.0000
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