Re: Simplifying multiple expressions

*To*: mathgroup at smc.vnet.net*Subject*: [mg108959] Re: Simplifying multiple expressions*From*: telefunkenvf14 <rgorka at gmail.com>*Date*: Thu, 8 Apr 2010 08:02:06 -0400 (EDT)*References*: <hphbmd$li4$1@smc.vnet.net> <hphq6r$1ij$1@smc.vnet.net>

On Apr 7, 6:27 am, Simon <simonjty... at gmail.com> wrote: > On Apr 7, 3:19 pm, Geico Caveman <spammers-go-h... at spam.invalid> > wrote: > > > A question arising out of laziness. > > > I have about 20 expressions that I want to simplify using the same set > > of assumptions. Is there an easy method for this ? > > Easiest way is if your objects _always_ satisfy some conditions is to > set the global assumptions: > > $Assumptions = ... > > otherwise you could define your own assumptions that you pass to > Simplify: > > myAssumptions = a>0 && b>1; > Simplify[ a + b > 1, myAssumptions] I like the global assumption route. If it matters, make sure you evaluate $Assumptions=True after performing your intended tasks, to reset. Here's a question I've had for a while... Why does $Assumptions=True make sense as the default setting? (I'm trying to understand this from the Mathematica point of view---would have guessed $Assumptions=Null) -RG