# Software: STRSCNE

**STRSCNE is a Matlab code for constrained nonlinear
systems of
equations**

**
F(x)=0 l<=x<=u**
**where F: R^n --> R^n, l and u are vectors of dimension n.
Non-existent lower and upper bounds, i.e.**

**entries of l and u equal to
minus o plus infinity, are allowed.**

**The algorithm is a globally
convergent procedure that combines Newton method and an elliptical
trust-region approach. The elliptical trust-region is defined employing a
scaling diagonal matrix D**

**and the trust-region subproblem is
approximately solved by the dogleg method. Only strictly feasible
iterates are generated.**

**Various input/output options are provided,
and we refer to the code itself for further documentation.**

**Authors:**

**Stefania Bellavia ***mailto:stefania.bellavia@unifi.it*

**Maria Macconi ***mailto:maria.macconi@unifi.it*

**Benedetta Morini ***mailto:benedetta.morini@unifi.it*

**STRSCNE code has non-commercial purposes. We assume no
responsibility for any errors that**

**may exist in the provided
routines. We welcome questions, comments, recommended changes and**

**bug reports.**

**If you use this code, the authors would appreciate your acknowledging
having done so in the reports, publications, theses, etc., resulting from their
use.**

**STRSCNE.m**

**Accompanying papers:**

** S.
Bellavia, M. Macconi, B. Morini, An
affine scaling trust-region approach to bound-constrained nonlinear systems
Applied Numer. Math., Vol. 44, pp. 257-180, 2003 **
** S. Bellavia, M. Macconi, B. Morini,
STRSCNE: A Scaled Trust Region Solver for Constrained Nonlinear Equations,
Computational Optimization and Applications,Vol. 28, pp.31-50, 2004.**