Re: How to get sqrt(Year^2)===Year?

*To*: mathgroup at smc.vnet.net*Subject*: [mg76001] Re: How to get sqrt(Year^2)===Year?*From*: Szabolcs <szhorvat at gmail.com>*Date*: Mon, 14 May 2007 05:49:02 -0400 (EDT)*Organization*: University of Bergen*References*: <f1s1v4$fip$1@smc.vnet.net> <f1upol$8hr$1@smc.vnet.net> <f26na5$421$1@smc.vnet.net>

Hatto von Aquitanien wrote: >> Simplify[x==Sqrt[x^2],x>0] >> >> hope this helps, Daniel > > Well, it helps in this circumstance. I believe Convert will do the same, > but I'm not sure if it works in all circumstances. In what circumstances? > I do wish there were > some way for Mathematica to know that something such as a physical constant > is real and positive. You didn't mention that you want to treat Year as a unit. > Perhaps doing that under all circumstances would > turn into a major performance hit, but it would be nice in circumstances in > which it is inappropriate to consider cases of x < 0, or x not real in > Sqrt[x]. $Assumptions = {Year > 0}