# How do I ensure a single character for \ldots

How do I ensure that \ldots comes out in the PDF as a single character?

I'm formatting a document for a publisher, who has given this condition in its formatting rules, but I do not know how I can do this in LaTeX.

I'm using MiKTeX 2.9

EDIT: Yes the question could be phrased as: is it possible for \ldots to produce a single "triple point glyph" rather than 3 separate dots (like "..."), since that's what it currently does.

Following the suggestion of kahen, I tried with XeLaTeX and the ellipsis character "…" as well as the \ldots command. Both worked and looked the same.

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I don't understand your request. Could you please explain in more detail? –  Gonzalo Medina Oct 26 '11 at 18:11
I think that the question is: "Does \ldots produce the single character (tripple point glyph?) or three periods?" –  Yossi Farjoun Oct 26 '11 at 18:13
If you use XeTeX, you can enter the ellipsis character directly into your document, but it will not look the same as \ldots. I don't think there is a way to get \ldots as a single glyph unless your font has a properly spaced out ellipsis in it. –  kahen Oct 26 '11 at 18:23
Check out this thread on the XeTeX mailing list as well: tug.org/pipermail/xetex/2010-December/019576.html –  kahen Oct 26 '11 at 18:41

The command \ldots, which works both in text mode and in math mode, will create a single glyph in xelatex and lualatex, assuming you're using a font that knows how to set character U+2026, "Horizontal Ellipsis."

In an earlier version of this answer, I mistakenly referred to what's created in pdflatex by the \ldots command as a "single glyph". In fact, it's composed of three separate dots, concatenated by non-breaking whitespace. Thus, while it's not a single glyph in the narrow, technical sense, it behaves like one for typesetting purposes. For instance, it won't ever get broken up across two lines.

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\ldots does not produce a single glyph in the resulting PDF file. It's produced by three peroids with manual space between them. Hence if you copy to a plain text file, you'll get . . . or something similar. –  kahen Oct 26 '11 at 18:26
Is this true? I'm able to select each period/dot in \ldots when I view a PDF. \ldots defaults to either \mathellipsis or \textellipsis, depending on whether you're in math mode or not, both of which are comprised of three individual dots. –  Werner Oct 26 '11 at 18:28
The publisher gave no other rules in regard to this. But with Xelatex and \ldots it works to produce a single glyph. –  user8868 Oct 26 '11 at 18:59
Glad that xelatex is working for you. I know there's a unicode code for "textellipsis", so that's why I was thinking that it was a single glyph. –  Mico Oct 26 '11 at 19:01
@Werner: I strongly suspect the publisher cares mostly about the dots not getting broken up across lines. The OP mentioned that ellipses have to be a "single character" -- this would be satisfied by a single glyph, but also by any construct that will not ever get broken up (in the pdf file, of course). –  Mico Oct 26 '11 at 19:43

You could use the dots family from the MnSymbol package; in the following example I used \hdots to define a new command \Ldots to produce the same result as \hdots, but using lowered instead of centered dots (I used \mathop in my definition to give the symbol the spacing corresponding to a standard operator, but you could replace it with \mathord to get the same spacing as \hdots):

\documentclass{article}
\usepackage{MnSymbol}

\newcommand\Ldots{\mathop{\lower.5ex\hbox{$\hdots$}}}

\begin{document}

$a\hdots b$

$a\Ldots b$

\end{document}

This remark is on page 64 of the The Comprehensive LaTeX Symbol List :

Also, unlike most of the other dot symbols in this document, MnSymbol’s dots are defined as single characters instead of as composites of multiple single-dot characters.

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Unlike \ldots, this creates three dots which are centered vertically. –  diabonas Oct 26 '11 at 18:35
@diabonas: good point. I've updated my answer accordingly. –  Gonzalo Medina Oct 26 '11 at 18:46
Some quick tests shows that using \smash{\raisebox{-.5ex}{$\hdots$}} pushes it down to the baseline. –  Werner Oct 26 '11 at 18:47