Print indexed (by subscript) variable name systematically

Question

I have some variables : Subscript[S, 1], Subscript[S, 2]...etc. But they are defined in a for loop like For[g = 1, g < 4, g++, Subscript[S, g] = g]; Later, I need to print each of the variable name, i.e Subscript[S, 1], Subscript[S, 2]...etc. But I can't find a systematic way to do this. For[g = 1, g < 4, g++, Print[HoldForm@Subscript[S, g]]]; doesn't work because it prints Subscript[S, g] always.

Any idea?

Just look at the code:

For[g = 1, g < 4, g++, Subscript[S, g] = g];
Print[Subscript[S, 1]]
Print[Subscript[S, 2]]
Print[Subscript[S, 3]]
For[g = 1, g < 4, g++, Print[Subscript[S, g]]];
Print[HoldForm@Subscript[S, 1]]
Print[HoldForm@Subscript[S, 2]]
Print[HoldForm@Subscript[S, 3]]
For[g = 1, g < 4, g++, Print[HoldForm@Subscript[S, g]]];
For[g = 1, g < 4, g++, Subscript[S, g] =.];

And this is the result:

enter image description here

Have a look at Defer and What are the most common pitfalls awaiting new users? — ssch, Sep 09 '13 at 13:16
You should use Do[..., {g, 3}] instead of For[g = 1, g < 4, g++, ...];. It's idiomatic, easier to read and maintain, and possibly faster. Or Map, if possible, or some other construct. — Volker, Sep 09 '13 at 13:17
Just HoldForm/Defer the S part: Subscript[S, 3] = 4; g = 3; Subscript[Defer[S], g] — ssch, Sep 09 '13 at 13:32
You may benefit from this answer which adds automatically symbolic elements with subscript. http://mathematica.stackexchange.com/questions/22376/how-to-define-a-vector-with-automatically-added-symbolic-elements-with-subscript — s.s.o, Sep 09 '13 at 14:05

score 3 · Answer 1 · answered Sep 09 '13 at 14:10

Some options:

Table[Subscript[HoldForm @ S, i], {i, 3}]

Table[With[{i = i}, HoldForm @ Subscript[S, i]], {i, 3}]

Table[i /. x_ :> HoldForm @ Subscript[S, x], {i, 3}]

You could also use Defer as ssch mentioned if you want to be able to use the output as input that evaluates.

Print indexed (by subscript) variable name systematically

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