How to shift characters and numbers in math mode to make them vertically centered around the formula axis

Question

In math mode, characters and numbers are placed on the baseline and develop upward and/or downward. How can they be centered vertically around the formula axis, as symbols such as + and = are?

For example in:

\documentclass{article}
\begin{document}
$n=0\ d(C,P)$
\end{document}

The n should be shifted upward, the 0, the d, the C, the comma and the P should instead be shifted downward. How can this be done automatically without having to manually set a raisebox value for each character and/or number?

Thank you for your help, it is very appreciated.

Edit: I excuse for being unclear about what I want. To clarify, my goal is to achieve what's displayed in the image that egreg posted in his comment. I hope it is clearer now, thank you again.

Are you talking about superscript and subscript? Like ^n or _n? — Sigur, Nov 17 '18 at 13:14
@Sebastiano, I have no idea. It is not clear what he wants. Maybe two separeted expressions: $n=0$, $d(C,P)$ or ${}^n=_{d(C,P)}$. — Sigur, Nov 17 '18 at 13:59
Please clarify what you mean by "how can [characters and numbers] be vertically centred around the formula axis like symbols are?" — Mico, Nov 17 '18 at 14:22
In this picture (click) top is the normal, bottom is with everything but the comma placed symmetrically with respect to the fomula axis. I hope you don't want that any longer. — egreg, Nov 17 '18 at 14:33
@Sebastiano The slash is to separate the two expressions without creating two math environments — Edoardo Serra, Nov 17 '18 at 15:21
@DũngVũ No, I want it to be like in the image that egreg linked in his comment, I've edited the question — Edoardo Serra, Nov 17 '18 at 15:28
@EdoardoSerra I won't tell, I don't want to be considered an accomplice in crimes against typography. — egreg, Nov 17 '18 at 17:00
@egreg - Are you implying that the answer I posted makes me a type-criminal? :-) — Mico, Nov 17 '18 at 18:27

Mico · Accepted Answer · 2018-11-17T16:55:31.850

The following screenshots show first what you say you want -- all letters, numerals, and commas centered vertically on the math axis -- and second what the normal typesetting approach produces, i.e., letters, numerals, and commas all placed on the baseline.

I very much hope that you will agree that the normal typesetting approach is to be preferred. Speaking for myself, centering commas vertically on the math axis borders on the preposterous...

\documentclass{article}

\usepackage[margin=0pt, paperwidth=3cm, paperheight=0.5cm]{geometry}
\usepackage{xcolor,graphicx}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}

% Command to center argument on math axis:
\newcommand\vc[1]{\vcenter{\hbox{$#1$}}} 

%% See https://tex.stackexchange.com/a/414613/5001 for source of the following code
%% Draw a line per font metric (#1 color, #2 vertical position, #3 label)
\newcommand{\drawmetric}[3]{\rlap{%
    \color{#1}\rule[#2]{2.55cm}{0.05pt}%
    \raisebox{#2}{\scalebox{0.3}{%
       \tiny\selectfont\sffamily #3}}%
  }}
\newcommand\drawallmetrics{%
  \drawmetric{red}{0pt}{baseline}%
  \drawmetric{blue}{1ex}{x-height}%
  \drawmetric{red}{\fontcharht\font`X}{cap-height}%
  \drawmetric{cyan}{\the\fontdimen22\textfont2}{math axis}}

\begin{document}

\noindent\rlap{ % 
  $\vc{n}=\vc{0}\ \vc{c}(\vc{C}\mathpunct{\vc{,}}\vc{u}\mathpunct{\vc{,}}\vc{P})$}
  \drawallmetrics{}

\noindent\rlap{ % 
  $n=0\ c(C,u,P)$}
  \drawallmetrics{}
\end{document}

How to shift characters and numbers in math mode to make them vertically centered around the formula axis

1 Answers1

Linked