Fonts & Character Sets ⇒ What is (hexdump: C2 A0) in the input tex file?

[user49915]

Consider the following input:

Code: Select all

\documentclass{standalone}
\begin{document}
$(\sigma_i, a_{i+1})$
\end{document}

All the chars are pure ASCII except the char right after the comma: it is not space, but the byte sequence C2 A0 and is shown in emacs as a kind of an underscore. I discovered it in a source latex file at several places but do not know the purpose of it. pdflatex seems to make a horizontal space, whereas xe|lua latex seem to ignore it. Any idea what was intended and why?

[Stefan Kottwitz]

That is a non-breaking space.

Perhaps an editor inserted it or it was copied with code from the Internet. I would replace it to be a normal space, such as via a script.

Stefan