$\newcommand{\Dev}{\operatorname{Dev}}$ $\newcommand{\dev}{\operatorname{dev}}$ $\newcommand{\grad}{\operatorname{grad}}$ $\newcommand{\divg}{\operatorname{div}}$ $\newcommand{\Ei}{\operatorname{Ei}}$ $\newcommand{\tr}{\operatorname{tr}}$

Use the “math” value for the type attribute to define a math controller. This controller allows users to use a mathematical expression that defines a function of time. Use the “t” parameter to reference time.

<load_controller id="1" type="math">
    <math>2.0*sin(pi*t)</math>
</load_controller>