# Sensitivity Analysis
Created by: Quan Gu (Xiamen University, China), Joel P. Conte (UCSD), Michele Barbato (LSU), Yong Li (UCSD)
This manual is intended to outline the basic commands currently available within the OpenSees interpreter for performing DDM (Direct Differentiation Method)-based response sensitivity analysis. This interpreter is an extension of the Tcl/Tk language for use with OpenSees. The existing Tcl commands for Finite Element response-only computation are described in the OpenSees user’s guide available online at http://opensees.berkeley.edu and, thus, are not repeated in this document. The notation used herein is the same as that used in the Tcl commands manual for response-only computation. Only new Tcl commands for DDM-based response sensitivity computation are presented and explained in detail.
This manual is subdivided as follows: