si – A com­pre­hen­sive (SI) units pack­age

This is a com­plete re-im­ple­men­ta­tion of units sup­port for LaTeX, build­ing on the ex­ist­ing SIu­nits and sistyle pack­ages. The pack­age in­cor­po­rates ideas from the units­def and numprint pack­ages, and aims to pro­vide a con­sis­tent and log­i­cal in­ter­face.
This is an ear­lier ver­sion of the pack­age now known as siu­nitx; that pack­age should be used for new ap­pli­ca­tions.