# [texhax] Description: \lbrace \rbrace

Barbara Beeton bnb at ams.org
Sat Nov 14 19:36:53 CET 2009

>         BB: with tex, < and > should (ordinarily) be used
> only to mean less than and greater than.
>
> they are used in html as angle brackets, but
> that's probably mainly because they are usually
> on keyboards.
>
> \langle and \rangle are the tex angle brackets;
> they are shallower than < and > and can be
> sized with \left and \right.

Paul: First of all, BB, thanks for your reply. Could you explain
what you mean by "shallow"? To extend the angle analogy, are they acute or
obtuse and, what effect do \left and \right achieve in this context? I was
under the impression that they matched the height of the brackets with that
of of the tallest object within.

"shallow": they are obtuse, taller than they
are wide.  they are about the same height and
width as parentheses, but instead of being
rounded, they have two straight arms.

as you point out, \left and \right have the
effect of making the brackets longer to match
the height of the tallest object within, with
the limitation that, because of the shape,
each larger size is a specific glyph -- they
can't be elongated (as can braces and brackets)
by adding more segments in the middle, at
least not the way they've been designed for
use with tex.
-- bb