### SNLSDP version 0 -- a MATLAB software for
sensor network localization

The software was last updated in 21 Oct 2008.

It implemented an SDP based approach with regularization for solving
sensor network localization problems. The algorithm first solves
an SDP relaxation (with regularization)
of the non-convex minimization problem (1), and use the SDP computed
solution as the starting point for a gradient descent method with
backtracking line search to solve the smooth unconstrained
problem (2).

This software package is designed for solving
small size senor network localization
problems with up to 200 sensors and a few thousands
given distances.

(1) min{ sum_{i,j} abs(norm(xi-xj)^2-dij^2)
+ sum_{k,j} abs(norm(ak-xj)^2-dkj^2) }

(2) min{ sum_{i,j} (norm(xi-xj)-dij)^2 + sum_{k,j} (norm(xj-ak)-djk)^2 }

where dij, dkj are distance data, xj is the position
of the jth sensor, and ak is the position of the kth anchor.

If you find SNLSDP useful in your work,
please cite the following paper:

[1] P. Biswas, T.-C. Liang, K.-C. Toh, T.-C. Wang, and Y. Ye,
Semidefinite programming approaches for sensor network localization
with noisy distance measurements,
IEEE Transactions on Automation Science and Engineering,
3 (2006), pp. 360--371.

- Copyright:
This version of SNLSDP is distributed under the GNU General Public License 2.0.
For commercial applications that may be incompatible with this license,
please contact the authors to discuss alternatives.
**SNLSDP-0.zip**

Please read.
Welcome to SNLSDP-0!
The software requires a few Mex files for execution.
You can generate (only need to be done once)
these executable files
as follows:
- Firstly, unpack the software:

unzip SNLSDP-0.zip
- Run Matlab in the directory SNLSDP-0
- In the Matlab command window, type:

>> cd SDPT3-4.0

>> Installmex

>> cd ..
- After that, to see whether you have installed SNLSDP correctly,
type:

>> startup

>> testSNLsolver
- By now, SNLSDP is ready for you to use.