Re: How to get rid of irrelevant Boolean variables from
- To: mathgroup at smc.vnet.net
- Subject: [mg94878] Re: [mg94828] How to get rid of irrelevant Boolean variables from
- From: Patrick Scheibe <pscheibe at trm.uni-leipzig.de>
- Date: Mon, 29 Dec 2008 06:40:41 -0500 (EST)
- References: <200812271204.HAA12519@smc.vnet.net>
Hi, maybe Mathematica doesn't assume that x and y are booleans? FullSimplify[(x && y) || ( ! x && y), Assumptions -> Element[{x, y}, Booleans]] Cheers Patrick On Sat, 2008-12-27 at 07:04 -0500, Vlad wrote: > Hi, > > I need to simplify a Boolean expression that looks like > > x && y || !x && y > > to y alone. I.e. the expression's truth value is independent of x so it should be left out. > > I've tried about every Mathematica function for dealing with Boolean expressions and couldn't do this. Also, > > Equivalent[x && y || !x && y, y]//TautologyQ > > gives False. This might be because the two expressions don't have the same number of variables (?). > > I have large truth tables so I would like to get rid of the irrelevant Boolean variables automatically. Does anyone know how to do this? > > Thanks >