RE: Product and Summation sign
- To: mathgroup at smc.vnet.net
- Subject: [mg66829] RE: [mg66788] Product and Summation sign
- From: "David Park" <djmp at earthlink.net>
- Date: Wed, 31 May 2006 06:31:57 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Larry, I'm replying this to both you and MathGroup because, as in most cases, once you further spell out your question there are many people there who know more about it than I do! I don't have the MathStatica package and don't know much about statistics. Perhaps SuperLog is a package function that has special formatting. Someone who works with the package will probably give you a better answer. It's possible to do a lot with Mathematica in the way of special formatting and implementing axioms, as rules say, so that abstract systems can be manipulated symbolically. But I won't go into it here because I'm not sure that is what you actually want to do. David Park djmp at earthlink.net http://home.earthlink.net/~djmp/ From: actuary at mchsi.com [mailto:actuary at mchsi.com] To: mathgroup at smc.vnet.net David: The "HoldForm" suggestion works. My question came about because I recently purchased "MathStatica" and was working through the material on Maximum Likehood Estimate. The examples contained in the test provided output from inputs that constructed a likelihood function that contained the product sign, just like one would write it out if doing by paper and pencil. Through the use of function "SuperLog", the Log of the likelihood function would be presented with a summation sign. None of the examples used "HoldForm". My first thought was that a Mathematica setting was not set correctly (StandardForm not checked--It was)and that was the reason my output looked different than that in the text. Any comments would be appreciated. Larry > Larry, > > Just use a HoldForm to stop evaluation. > > Sum[x[i], {i, 1, 50}] // HoldForm > > If you wish to manipulate an expression within a HoldForm you can use rules, > or you could try the ExpressionManipulation package at my web site below. > > David Park > djmp at earthlink.net > http://home.earthlink.net/~djmp/ > > From: actuary at mchsi.com [mailto:actuary at mchsi.com] To: mathgroup at smc.vnet.net > > While a Mathematica user for some time, use has been limited to number > crunching and not symbolic manipulations. I started to remedy this > over the weekend. > > I entered Sum[x[i],{i,1,50}] expecting to see a response with Summation > sign. Instead the output was x[1}+x[2]+x[3]+..... > > What do I need to do to get output that includes the Summation sign? > StandardForm was checked. > > Thanks. > > Larry > >