From reactions to differential equations

*To*: mathgroup at smc.vnet.net*Subject*: [mg93348] From reactions to differential equations*From*: zac <replicatorzed at gmail.com>*Date*: Tue, 4 Nov 2008 06:20:08 -0500 (EST)

Dear All, from some time now I=E1m working with more and more complex differential equations. Is there a package to transform a set of reaction-kinetic equations such as: { Subscript[a, i] + Subscript[b, j] -> Subscript[c, i, j], Subscript[a, i] + Subscript[c, i, j] -> 2 Subscript[a, i] + Subscript[b, j], Subscript[b, i] + Subscript[c, j, i] -> 2 Subscript[b, i] + Subscript[c, j] } to differential equations expressing the growth of a_i, b_i and c_i,j, regarding that I leave the parameters i and j undefined? I am fully aware of software packages like COPASI and Systems Biology that are available, but I think they are far more complex than what is needed here, and furthermore I would like to understand the method how these reactions are actually converted to diff.equations. Which I completely miss if I'm to rely on a concealed algorithm. I've already started to write a parser in Mathematica, but it became too cumbersome after a point to deal with indexed variables (without indices it is fairly simple), and I really don't want to invent something that (perhaps) already exists on the field. Any ideas? Istvan Zachar

**Follow-Ups**:**Re: From reactions to differential equations***From:*"Tamara Ursem" <tursem@gmail.com>