Hi, I've developed a Lua 5.1 interface to the UCAR UDUNITS-2 unit conversion library (http://www.unidata.ucar.edu/software/udunits/) which is advertised as: UDUNITS supports conversion of unit specifications between formatted and binary forms, arithmetic manipulation of units, and conversion of values between compatible scales of measurement. Source is available via bitbucket https://bitbucket.org/djerius/lua_udunits2 An autotooled tarball is available at https://bitbucket.org/djerius/lua_udunits2/downloads Diab -- Diab Jerius <djerius@cfa.harvard.edu> Smithsonian Astrophysical Observatory