Re: Bernoulli variable algebra
- To: mathgroup at smc.vnet.net
- Subject: [mg46530] Re: Bernoulli variable algebra
- From: drbob at bigfoot.com (Bobby R. Treat)
- Date: Sun, 22 Feb 2004 11:27:28 -0500 (EST)
- References: <c16m89$5pd$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Use some special symbol (rather than x) for your Bernoulli variables. I'll use "binary": binary*binary ^= binary; Unprotect[Power]; binary^_ := binary Protect[Power]; Expand[binary*(1 + binary)^10] 1024*binary Bobby jmyers6761 at aol.com (JMyers6761) wrote in message news:<c16m89$5pd$1 at smc.vnet.net>... > I have been working on a Mathematica package used to predict the reliability of > complex redundent systems. The calculations, which are done symboliclly, become > quite complex. Since all of the variables used are Bernoulli variables, i.e. > take on only values of 0 or 1, the expressions must be simplified by use of the > rule x_^n_->x. My problem is this, the expressions are complex and large and, > as a result the Mathematica Kernal runs out of memory trying to expand the > expressions. I know, from other techniques, that the resulting expressions > after application of the x_^n_->x rule are still large (> 1000 terms) they are > not unmanageable. (The expressions prior to applying the rule might be on the > order of 10^6 terms) If a technique could be devised for accomplishing the > effect of the above transformation without first requiring the full expansion > of the expressions it would be possible to greatly simplify the required > analysis. Is anyone aware of a technique for the simplification of algebraic > expressions of Bernoulli variables without requiring expansion of the > expression first? > > Any hints would be greatly appreciated. > Thankyou, > Al Myers