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<h3 class="section">4.3 Another numerical gradient function</h3>
<p><a name="index-numgradient-81"></a>
<h4 class="subheading">Helptext:</h4>
<p><a name="XREFnumgradient"></a>
<pre class="verbatim">numgradient(f, {args}, minarg)
Numeric central difference gradient 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)
\"f\" may be vector-valued. If \"f\" returns
an n-vector, and the argument is a k-vector, the gradient
will be an nxk matrix
Example:
function a = f(x);
a = [x'*x; 2*x];
endfunction
numgradient(\"f\", {ones(2,1)})
ans =
2.00000 2.00000
2.00000 0.00000
0.00000 2.00000
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