# [texhax] floor and ceiling

Kevin Godby godbyk at gmail.com
Thu Mar 5 00:04:59 CET 2009

On Wed, Mar 4, 2009 at 4:57 PM, P. R. Stanley <prstanley at ntlworld.com> wrote:
>
>>\lfloor is the left side of the the floor bracket, and \rfloor the
>>right. \lfloor looks kind of like a capital L, while \rfloor is the
>>mirror image. If the innards of the bracket is tall (like a \frac,
>>for example) using $\left\lfloor \frac{n}{2} \right\rfloor$ would be
>>best. \ceil is similar.
>>
>>Great! Thanks. What do lceil and rceil look like?

To continue with Robert's L-based description: \lceil and \rceil look
just like \lfoor and \rfloor, but they're flipped vertically (that is,
reflected about their central horizontal axis).  So the \lceil looks
like an inverted capital L and the \rceil looks like turned capital L
(i.e., an L that has been rotated 180 degrees).

The floor and ceiling brackets don't have serifs -- just two
perpendicular lines.  To me, they look more like square brackets [ and
] with either the top or bottom horizontal strokes removed.  (The
bottom strokes are removed for ceiling, and the top strokes are
removed for floor.)

--Kevin Godby