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Computing a Jacobian With Constants that Change

Purpose
In this example we use two levels of taping so that a derivative can have constant parameters that can be changed. To be specific, we consider the function $f : \B{R}^2 \rightarrow \B{R}^2$ $$f(x) = p \left( \begin{array}{c} \sin( x_0 ) \\ \sin( x_1 ) \end{array} \right)$$ were $p \in \B{R}$ is a parameter. The Jacobian of this function is $$g(x,p) = p \left( \begin{array}{cc} \cos( x_0 ) & 0 \\ 0 & \cos( x_1 ) \end{array} \right)$$ In this example we use two levels of AD to avoid computing the partial of $f(x)$ with respect to $p$, but still allow for the evaluation of $g(x, p)$ at different values of $p$.
Input File: example/general/change_param.cpp