Correctly typesetting a tilde

Question

How do I set the tilde (~) character correctly in LaTeX?

There’s a question discussing that on Stack Overflow, with a lot of answers. But dare I say it? They all suck:

• \textasciitilde is too high,
• \texttildelow is too low.
• $\sim$ can be tweaked to look more or less acceptable: {\raise.17ex\hbox{$\scriptstyle\sim$}} – but even that is a hack and uses the wrong symbol.

The point is – the tilde character is definitely an existing glyph in any font I am tempted to use. How can I just access and typeset that character, please? Without resorting to some other, similar-looking glyph that first needs to be nudged into place using a cunning combination of font size and raised boxes?

There must be a possibility to access that glyph directly from the font definition.

To demonstrate, look at this screenshot which attempts simply to display a C++ destructor of a type T (~T):

Compare this with the symbol we get in the browser: ~ – that’s what I want.

Answer 1

It all depends on what do you want this glyph to stand for.

If you want to use it in an url then add \usepackage{url} (or hyperref) to your preamble and then use \url{http://example.com/~user}.

If you want to use it inside a math formula as some kind of relation then use $a \sim b$.

According to the "Comprehensive Symbols List", to get a vertically centered ~ you can use \texttildelow in any font other than Computer Modern, txfonts, and pxfonts. For example the following does the trick for typesetting a C++ destructor

\usepackage{times}
\usepackage{textcomp}

\texttildelow T

Answer 2

according to the Comprehensive LaTeX Symbol List, \texttildelow "produces a vertically centered “~” in most fonts but a baseline-oriented “~” in Computer Modern, txfonts, pxfonts, and various other fonts originating from the TEX world." So to produce a centered Tilde, one can use something like

{\fontfamily{ptm}\selectfont\texttildelow}T()

(Taken from the symbol list source code. A different font might give a better result, depending on what the main font of your text is.)

Answer 3

For completeness’ sake: the accepted solution only seems to work with T1 fonts. When using XeTeX with the fontspec package, it once again displays a tilde at baseline level.

Luckily, there’s a simple workaround: When using a TTF or OTF font with fontspec, \char`~ works as expected. Unfortunately, this solution only works for fontspec, not with T1 fonts.

Answer 4

If you want to write in computer modern and still use the tilde, just load lmodern; them nice folks seem to consider it a bug, and \textasciitilde produces the vertically centred tilde.