I want to make horizontal and vertical curly braces to show up simultaneously just outside a matrix, but it only works when I use one or the other, instead of both.
I use \left.\right\}
for vertical braces, and \underbrace{}_{}
for horizontal ones.
Here's my attempt:
\begin{align*}
\underset{m\times n}{0}=
\underbrace{\left.
\begin{bmatrix}
0 & 0 & \dots & 0\\
0 & 0 & \dots & 0\\
\dots & \dots & \dots & \dots\\
0 & 0 & \dots & 0
\end{bmatrix}
\right\}\text{$m$ rows}}_\text{$n$ columns}
\end{align*}
Obviously, the "n columns" one is too long: I want it to cover from the first element to the last, not all the way to the end of the vertical brace. How can I fix it?
Best Answer
I wouldn't be so fussy about showing the definition of a zero matrix like that, but you know your students…
The trick is to pretend that the
\underbrace
part does not really extend below the baseline, so\right\}
will just take care of the upper part, but it acts symmetrically around the formula axis.A
\vphantom
makes the formula with the right depth so not to destroy the spacing with the following material.I applied
\,
and\!
to avoid the underbrace being too wide and collide with the right brace.Don't use
align
for single displayed formulas.