3

Putting primes and commas together in subscript results in awkward spacing --- the space between a primed item and the following comma is exceedingly large compared to the space after.

The same happens with any superscripts in subscripts, but with primes this is especially jarring.

This does not occur outside of subscripts. Is there any simple remedy?

MWE:

\documentclass[12pt]{article}
\begin{document}
{
\Huge
\[
  f_{a,b',c}\quad a, b', c
\]
}
\end{document}

enter image description here

tomasz
  • 825
  • 2
    f_{a,b'\!,c} would be an easy fix. Actually this does happen in textstyle also; it's just not as noticible. You can use a, b'\!, c there as well. – Sandy G Mar 19 '21 at 22:00
  • Just a simple curiosity. Why do you use \Huge{...} out the math-formula? – Sebastiano Mar 19 '21 at 22:03
  • @SandyG: sure, sure, but I meant something less ad hoc. Doing this sort of thing once is okay, but maintaining a longer document where you have lots of primed subscripts this way would be a nightmare. – tomasz Mar 19 '21 at 22:03
  • @Sebastiano: So it's easier to see the result without zooming. – tomasz Mar 19 '21 at 22:03
  • @tomasz Ah....I had not understood the reason :-) – Sebastiano Mar 19 '21 at 22:10
  • 1
    the braces after \Huge though are misleading as the font size applies to the whole document not just the brace group, although not clear here as there is nothing after } – David Carlisle Mar 19 '21 at 23:06
  • @DavidCarlisle: Thanks, I did not know that. I had actually never used the size commands before. I fixed the MWE. – tomasz Mar 20 '21 at 00:08

1 Answers1

2

You can use from amsmath, the command \negthickspace.

\documentclass[12pt]{article}
\usepackage{amsmath}
\begin{document}
\[
  f_{a,b'\negthickspace,c}\quad a, b', c
\]

\end{document}

enter image description here

Sebastiano
  • 54,118
  • Thanks, this looks much better (and also a bit nicer than the vanilla ! solution), but I was wondering if there is a solution that would not require typing an extra command for every single prime comma combination (like a package that would just magically do this). – tomasz Mar 20 '21 at 00:11
  • @tomasz It is possibile but or we use a \newcommand or we must use very complicated strategies that I don't know about. – Sebastiano Mar 20 '21 at 20:26
  • You can see, for example, here in this link with any package that I not know the mechanicism: https://tex.stackexchange.com/questions/444038/merge-double-subscripts-in-macro-with-second-subscript-passed-as-argument or – Sebastiano Mar 20 '21 at 20:33