How to align superscripts?

Question

I have an expression like

$$\eta^{[\alpha\beta}_{\phantom{\alpha\beta}\rho}h^{\sigma]}A^\rho$$

and I would like that all the indices alpha, beta, sigma and rho appear on a same line. If someone have a suggestion it will be great!

Welcome! Do you want those [] to be rendered? What do they mean? Please do not use $$ $$ but \[ \] as the first is deprecated since years. — LaRiFaRi, Mar 17 '16 at 11:17
Without those brackets, \[\eta^{\alpha\beta}_{\rho}h^{\sigma}A^\rho\] should be just fine. If it isn't, you will have to show us an MWE please! — LaRiFaRi, Mar 17 '16 at 11:19
Hmmm... I can't really parse this expression --- can't really see what it "means" mathematically. Is the $h$ multiplying $\alpha\beta$ and has a pre-subindex $\rrho$ and exponent $\sigma$? or is $\sigma$ with two left-subindex multiplying $\alpha\beta$? I suggest a rewrite ;-) — Rmano, Mar 17 '16 at 12:00

AboAmmar · Answer 1 · 2016-03-17T11:50:28.940

6

What you need is \hphantom instead of just a \phantom:

\documentclass{article}
\begin{document}
\[
   \eta^{[\alpha\beta}_{\hphantom{\alpha\beta}\rho}h^{\sigma]}A^\rho
\]
\end{document}

edited Mar 17 '16 at 11:50

answered Mar 17 '16 at 11:43

AboAmmar

46,352
4
58
127

score 4 · Answer 2 · answered Mar 17 '16 at 11:56

If the \phantom term is omitted, the superscript terms will be aligned correctly without further ado. The following screenshot shows (a) your original expression, (b) a first alternative that features the subscript \rho term far from \eta, and (c) a second alternative where the \rho subscript is placed closer to \eta.

\documentclass{article}
\usepackage{amsmath}
\begin{document}
\begin {align*}
\text{Orig.}\qquad &
\eta^{[\alpha\beta}_{\phantom{\alpha\beta}\rho}h^{\sigma]}A^\rho\\
\text{Alt.\ 1} \qquad&
{\eta^{[\alpha\beta}}_{\mkern-8mu\rho} \, h^{\sigma]} A^\rho\\
\text{Alt.\ 2} \qquad&
\eta^{[\alpha\beta}_{\rho} h^{\sigma]} \! A^\rho
\end{align*}
\end{document}

Steven B. Segletes · Answer 3 · 2016-03-17T14:02:02.413

2

It is not ideal, but you could add a \mystrut to every base and embrace {} the base. EDITED to address barbara's concern by making the strut a custom \mystrut that does not go below the baseline.

\documentclass{scrreprt}
\def\mystrut{\rule{0pt}{\the\ht\strutbox}}
\begin{document}
\[{\mystrut\eta}^{[\alpha\beta}_{\phantom{\alpha\beta}\rho}
  {\mystrut h}^{\sigma]}{\mystrut A}^\rho\]
\end{document}

edited Mar 17 '16 at 14:02

answered Mar 17 '16 at 11:21

Steven B. Segletes

237,551

1

the subscripted \rho is lower; that's not really desirable. – barbara beeton Mar 17 '16 at 12:22
@barbarabeeton addressed with a custom upward-only \mystrut. – Steven B. Segletes Mar 17 '16 at 14:02

score 1 · Answer 4 · edited Apr 13 '17 at 12:35

In this particular construction, you can set the sub-script to \eta as separate sub-script to {} (nothing). The combination of the super- and sub-script is causing a vertical shift of the scripts:

\documentclass{article}

\begin{document}

\[
  \eta^{[\alpha\beta} \!\! {}_\rho \, h^{\sigma]} A^\rho
\]

\end{document}

I've added some horizontal spacing to simulate the [dis]association of the \rho sub-script with \eta [h], but that's up to personal preference.

How to align superscripts?

4 Answers4