Re: Mathematica and Symbolic Manipulation

*To*: mathgroup at smc.vnet.net*Subject*: [mg114534] Re: Mathematica and Symbolic Manipulation*From*: Richard Fateman <fateman at cs.berkeley.edu>*Date*: Tue, 7 Dec 2010 06:44:59 -0500 (EST)*References*: <ictg1v$mkc$1@smc.vnet.net> <id01n6$h89$1@smc.vnet.net> <idhivl$923$1@smc.vnet.net>

On 12/5/2010 6:49 PM, olfa wrote: > On 29 nov, 12:10, Andrea<btlgs2... at gmail.com> wrote: >> On Nov 28, 12:56 pm, olfa<olfa.mra... at yahoo.fr> wrote: >> >>> Dear All, >> >>> I'm facing a big problem with Mathematica because I need to use it >>> SYMBOLICALLY for many functions like: >>> 1)Nest[f,x,i] (without knowing the value of i) >>> 2)Table[exp,{index,i,n}] (without knowing the values of i and n) >>> 3)Rest[m] such that m is a symbolic list (without knowing its concrete >>> elements) >> >>> How to deal with that? >>> Thank you for your help. >> >> I olfa, >> what do you mean for simbolically use of these functions? >> When you write them Mathematica just keep them unevaluated, just >> writing some message that you can suppress ( look at tutorial/Messages >> section of reference for info). >> This is not the result you want? >> Andrea > > Hi andrea > Here is an example of what I need to do: > > Reduce[Nest[f,v,j]==Nest[f,vP,jP]&& j>=jP,{vP}] > > should return vP=Nest[f,v,j-jP] > > Thanks > > Calculation with objects of "symbolic" extent is different from the usual setup in Mathematica or other computer algebra systems. Another kind of calculus must be used. For example I have written programs that deal with matrices of size nXn where n is a symbol; one can demonstrate that the inverse of the nxn identity matrix is itself. One can also talk about block matrices etc. www.eecs.berkeley.edu/~fateman/papers/symmat2.pdf RJF