Why not just sqlclr + any of the brazillion c# expression parsers?

https://www.google.com/#sclient=psy-ab&hl=en&source=hp&q=c%23+math+expression+parser&pbx=1&oq=c%23+math+express&aq=0&aqi=g2g-C1g-jC1&aql=&gs_sm=e&gs_upl=0l0l1l79l0l0l0l0l0l0l0l0ll0l0&bav=on.2,or.r_gc.r_pw.r_cp.,cf.osb&fp=ea0e067728996111&biw=1231&bih=652

More generally, why chew up db cycles (affecting all db users) with this at all, rather than put the dotnet code in the client app itself (affecting only the user who needs it)?