2nd European Workshop on Automatic Differentiation

Thursday November 17- Friday November 18, 2005

Whitworth Conference Centre

Cranfield University (Shrivenham Campus)

Defence Academy of the UK

Shrivenham, Swindon

Uwe Naumann (RTWH Aachen)

Min-ops Derivative Accumulation is NP-complete

Abstract: We show that the combinatorial optimization problem that aims to accumulate
derivatives with a minimal number of floating-point operations is NP-complete by reduction from ENSEMBLE COMPUTATION. The proof is based on a possible algebraic dependence between local partial derivatives of the elemental functions.

Time permitting, we present a brief overview of research activities in our group. In particular, we give an update on the ongoing development of the adjoint NAGWare Fortran 95 compiler.

Slides: NaumannNov05.pdf