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<h3 class="section">4.2 Higher order numerical derivatives</h3>

<p><a name="index-deriv-76"></a>
<!-- deriv ../inst/deriv.m -->
<a name="XREFderiv"></a>

<div class="defun">
&mdash; Function File: <var>dx</var> = <b>deriv</b> (<var>f, x0</var>)<var><a name="index-deriv-77"></a></var><br>
&mdash; Function File: <var>dx</var> = <b>deriv</b> (<var>f, x0, h</var>)<var><a name="index-deriv-78"></a></var><br>
&mdash; Function File: <var>dx</var> = <b>deriv</b> (<var>f, x0, h, O</var>)<var><a name="index-deriv-79"></a></var><br>
&mdash; Function File: <var>dx</var> = <b>deriv</b> (<var>f, x0, h, O, N</var>)<var><a name="index-deriv-80"></a></var><br>
<blockquote><p>Calculate derivate of function <var>f</var>.

        <p><var>f</var> must be a function handle or the name of a function that takes <var>x0</var>
and returns a variable of equal length and orientation. <var>x0</var> must be a
numeric vector or scalar.

        <p><var>h</var> defines the step taken for the derivative calculation. Defaults to 1e-7.

        <p><var>O</var> defines the order of the calculation. Supported values are 2 (h^2 order)
or 4 (h^4 order). Defaults to 2.

        <p><var>N</var> defines the derivative order. Defaults to the 1st derivative of the
function. Can be up to the 4th derivative.

        <p>Reference: Numerical Methods for Mathematics, Science, and Engineering by
John H. Mathews. 
</p></blockquote></div>

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