Re: Subscript on plus expression

*To*: mathgroup at smc.vnet.net*Subject*: [mg128713] Re: Subscript on plus expression*From*: "Dave Snead" <dsnead6 at charter.net>*Date*: Mon, 19 Nov 2012 04:10:17 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-newout@smc.vnet.net*Delivered-to*: mathgroup-newsend@smc.vnet.net*References*: <20121117084935.868E56AF3@smc.vnet.net> <k8a898$89n$1@smc.vnet.net> <20121118221341.5BC226958@smc.vnet.net>

Nasser --, I'm using these as tensor indices. Although Bob Hanlon offered a workaround (thanks Bob) Format[Subscript[arg_Plus, k_]] := Subscript["(" <> StringJoin @@ Riffle[ToString /@ (List @@ arg), " + "] <> ")", k] Subscript[a + b + 2, k], I think the folks at Mathematica should fix this and insert the parentheses. The output of Subscript[Plus[a,b],k] should not be represented as Plus[a,Subscript[b,k]]! -- Dave -----Original Message----- From: Nasser M. Abbasi Sent: Sunday, November 18, 2012 2:13 PM To: mathgroup at smc.vnet.net Subject: [mg128713] Re: Subscript on plus expression On 11/18/2012 3:03 AM, Dave Snead wrote: > Hi, > > Mathematica fails to parenthesize the a+b in > Subscript[Plus[a,b],k] > > so the output looks identical to > Plus[a,Subscript[b,k]] > > Is this a bug? > Is there an option to force the parentheses? > > Thanks in advance, > Dave Snead > > > Actually, just typing (a+b) k and then hitting ENTER will result in a+b k i.e. the () are gone. Same effect you showed. It might be because subscript are meant to be applied to an atomic symbol and not combined expression like a+b. I do not know. I am not even sure what (a+b)_k is supposed to mean, math wise. Is this meant to be on the code or in a text cell? If it is in the code itself, how will it be used? --Nasser

**References**:**Plotting a series of Roots***From:*William Duhe <wjduhe@loyno.edu>

**Re: Subscript on plus expression***From:*"Nasser M. Abbasi" <nma@12000.org>