SAS IML does it too.
Here is an example,
http://support.sas.com/documentation/cdl/en/imlug/59656/HTML/default/viewer.htm#genstatexpls_sect13.htm
The estimation of LAV can be casted into a linear programming problem. Any solver with interior-point methed can solve a reasonable big problem within a reasonable time.
The estimation of LAV can be casted into a linear programming problem. Any solver with interior-point methed can solve a reasonable big problem within a reasonable time.