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I want to express the following function:

$z^{(1)}=w^{(1)}a^{(0)}+b^{(1)}$

I have read in Mathematica documentation that Symbolize can be used to define variables with superscripts. I would like to define a function that uses $w^{(1)}$, $a^{(0)}$ and $b^{(1)}$ as dependent variables.

This is what I have tried:

<< Notation`
    Symbolize[NotationTemplateTag[z^(1)]]
    Symbolize[NotationTemplateTag[w^(1)]]
    Symbolize[NotationTemplateTag[a^(0)]]
    Symbolize[NotationTemplateTag[a^(1)]]
    Symbolize[NotationTemplateTag[b^(1)]]

And then I try to define the variable as:

(z^(1))[w^(1)_, a^(0)_, b^(1)_] := w^(1) a^(0) + b^(1)

but I get $Failed.

Specifically: Failed function definition

Is it possible to define a function named with a superscript and having as dependent variables symbols with superscripts? I so, what is not properly done above?

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  • 1
    $\begingroup$ I suspect that z^(1) is interpreted as Power[z,1] and simplifying to z automatically. You could try Trace and FullForm. $\endgroup$
    – mikado
    Sep 3, 2022 at 11:35
  • $\begingroup$ I am actually entering z^(1) using control+^, so that z^(1) shall be theoretically treated as a single symbol. I have attached a screenshot. $\endgroup$
    – M.E.
    Sep 3, 2022 at 11:43
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    $\begingroup$ I strongly encourage you to use another notation. This may look good, but you are setting yourself up for a lot of unnecessary work and restrictions down the road when you actually have to do any computation on these symbols. The best way is normally indexed variables such as z[1] instead. $\endgroup$
    – MarcoB
    Sep 3, 2022 at 15:02
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    $\begingroup$ (+1) I think the generalized question, How can one use symbols created by the Notation package as pattern names?, is good. I wouldn't be surprised if there's already a similar Q&A on site, given how often the Notation package is used. (Bob Hanlon's answer seems to address output formatting only, which is not the same as input formatting.) I generally avoid programming with the Notation package for the reasons @MarcoB points out. But it does have its uses, which shouldn't be dismissed. $\endgroup$
    – Michael E2
    Sep 3, 2022 at 15:42
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    $\begingroup$ Found one: Does this answer your question? How to use subscript in pattern names? $\endgroup$
    – Michael E2
    Sep 3, 2022 at 15:44

1 Answer 1

Reset to default
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ClearAll["Global`*"]

Format indexed variables

(Format[#[n_]] := Superscript[#, Row[{"(", n, ")"}]]) & /@ 
  {z, w, a, b};

The function definition is

z[1][x_, y_, z_] := x*y + z

With your specific arguments

z[1][w[1], a[0], b[1]]

enter image description here

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