Re: Convert from String to variable

*To*: mathgroup at smc.vnet.net*Subject*: [mg70246] Re: [mg70229] Convert from String to variable*From*: "Peng Yu" <pengyu.ut at gmail.com>*Date*: Mon, 9 Oct 2006 01:56:02 -0400 (EDT)*References*: <200610080604.CAA11869@smc.vnet.net> <NDBBJGNHKLMPLILOIPPOAECNFDAA.djmp@earthlink.net>

On 10/8/06, David Park <djmp at earthlink.net> wrote: > Peng, > > Just use Symbol. > > Symbol["a" <> ToString[1] <> ToString[2] <> ToString[3]] > Head[%] > a123 > Symbol What I really intent to define is a function like the following. l, m and n could go from 0 to any positive integer. Here the parameter list of CD should also be changed correspondingly. CD[Ith_, z_, d_, Ith0_, a000_, a001_, a002_, a010_, a011_, a012_, a020_, a021_, a022_, a100_, a101_, a102_, a110_, a111_, a112_, a120_, a121_, a122_, a200_, a201_, a202_, a210_, a211_, a212_, a220_, a221_, a222_] := Sum[ToExpression["a" <> ToString[l] <> ToString[m] <> ToString[n]]*( Ith - Ith0)^l*z^(2*m)*d^(n), {l, 0, 2}, {m, 0, 2}, {n, 0, 2}] I tried this, but it is not working. The difficulty is in the left hand side. Can I write a function to define a set of other functions? CD[Ith_, z_, d_, Ith0_, Flatten@ Table[ToExpression["a" <> ToString[l] <> ToString[m] <> ToString[n] <> "_"], {l, 0, 2}, {m, 0, 2}, {n, 0, 2}]] := Sum[ToExpression["a" <> ToString[l] <> ToString[m] <> ToString[n]]*(Ith - Ith0)^l*z^( 2*m)*d^(n), {l, 0, 2}, {m, 0, 2}, {n, 0, 2}]

**References**:**Convert from String to variable***From:*"PengYu.UT@gmail.com" <PengYu.UT@gmail.com>