**Optimal-value function tools**

OptValFunc toolbox aims at operating an optimal-value function in the form

\[\psi(x) = \min_{y} \{f(x, y):~g(x; y)\leq 0\},\nonumber\] where $x\in\mathbb{R}^{n_x},y\in\mathbb{R}^{n_y}$ and $g:\mathbb{R}^{n_x\times n_y}\rightarrow \mathbb{R}^{n_g}$. Read more in the menu-of-BiOpt. The toolbox provides two tools:

**SolOVF**solves the above minimization problem with providing the function values and corresponding optimal solutions.**PlotOVF**plots the graph of $\psi(x)$ along with $x$. Thus for the purpose of visualization, the dimension $n_x$ of $x$ must be 1 (for two dimensional space) or 2 (for three dimensional space). For example，