Brackets inside brackets with newline inside

Question

My question is how to achieve this effect in LaTeX? I tried various combinations of \right and \left but it does not work.

EDIT

Adding the code:

    $[introduces]m$ = $\left[ 
    o_1 = \left\lbrack[o_1 
    \newline
    o_2
    o_3] \right\rbrack
    o_2 = \lbrack \rbrack
    \right]$

You may consider this question https://tex.stackexchange.com/questions/50627/matrix-in-a-matrix — Cragfelt, Nov 19 '17 at 22:07

egreg · Accepted Answer · 2017-11-19T22:56:05.033

4

You could use array nested in array, but in this case I believe aligned is better:

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\begin{equation*}
\left[
\begin{aligned}
o_1 & \mapsto
  \left[
  \begin{aligned}
  o_1 & \mapsto 1 \\
  o_2 & \mapsto 0 \\
  o_3 & \mapsto 0
  \end{aligned}
  \right]
\\
o_2 & \mapsto
  \left[
  \begin{aligned}
  o_1 & \mapsto 1 \\
  o_2 & \mapsto 1 \\
  o_3 & \mapsto 0
  \end{aligned}
  \right]
\\
o_3 & \mapsto
  \left[
  \begin{aligned}
  o_1 & \mapsto 0 \\
  o_2 & \mapsto 0 \\
  o_3 & \mapsto 1
  \end{aligned}
  \right]
\end{aligned}
\right]
\end{equation*}

\end{document}

Without overshooting:

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\begin{equation*}
\begin{bmatrix}
\begin{aligned}
o_1 & \mapsto
  \begin{bmatrix}
  \begin{aligned}
  o_1 & \mapsto 1 \\
  o_2 & \mapsto 0 \\
  o_3 & \mapsto 0
  \end{aligned}
  \end{bmatrix}
\\
o_2 & \mapsto
  \begin{bmatrix}
  \begin{aligned}
  o_1 & \mapsto 1 \\
  o_2 & \mapsto 1 \\
  o_3 & \mapsto 0
  \end{aligned}
  \end{bmatrix}
\\
o_3 & \mapsto
  \begin{bmatrix}
  \begin{aligned}
  o_1 & \mapsto 0 \\
  o_2 & \mapsto 0 \\
  o_3 & \mapsto 1
  \end{aligned}
  \end{bmatrix}
\end{aligned}
\end{bmatrix}
\end{equation*}

\end{document}

edited Nov 19 '17 at 22:56

answered Nov 19 '17 at 22:10

egreg

1,121,712

The smaller brackets overshoot a bit at the top and the bottom. Is this on purpose? – Nov 19 '17 at 22:12
@marmot It's just the default output. I don't think it's bad. – egreg Nov 19 '17 at 22:12
But how to move it to left side? Like \noindent does it? – KompiKompi Nov 19 '17 at 22:31
@KompiKompi I don't think you want such a big object not to be displayed. – egreg Nov 19 '17 at 22:41
I don’t like the overshoot of the inner brackets: may I respectfully suggest adding \noalign{\smallskip} at the top and bottom of the outer aligned? :-) – GuM Nov 19 '17 at 22:51
@GuM You can suggest. ;-) I can do it differently. ;-) – egreg Nov 19 '17 at 22:53

Bernard · Answer 2 · 2017-11-19T22:37:32.990

3

Like this?

\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage{mathtools, booktabs}

\begin{document}

\[ \begin{bmatrix}
    \addlinespace
    \;o_1 & \longmapsto \begin{bmatrix}
      o_1 & \longmapsto 1 \\
      o_2 & \longmapsto 0 \\
      o_3 & \longmapsto 0
    \end{bmatrix}\;
    \\
    \addlinespace
    \;o_2 & \longmapsto \begin{bmatrix}
      o_1 & \longmapsto 1 \\
      o_2 & \longmapsto 1 \\
      o_3 & \longmapsto 0 \\
    \end{bmatrix}\;\\
    \addlinespace
    \;o_3 & \longmapsto \begin{bmatrix}
      o_1 & \longmapsto 0 \\
      o_2 & \longmapsto 0 \\
      o_3 & \longmapsto 1
    \end{bmatrix} \\
    \addlinespace
  \end{bmatrix}\; \]

\end{document}

edited Nov 19 '17 at 22:37

answered Nov 19 '17 at 22:15

Bernard

271,350

is there an extra \; after the first inner bmatrix? – Nov 19 '17 at 22:21
Yes, I added some padding between the inner matrices and the outer one, for aesthetic reasons. – Bernard Nov 19 '17 at 22:30
but shouldn't it be also then with the second and third? as it stands alignment is weird – Nov 19 '17 at 22:31
You're right. I guess I tgought of it as <{\;} in the preamble of an array. I'll fix that. – Bernard Nov 19 '17 at 22:35

AboAmmar · Answer 3 · 2017-11-19T22:38:05.803

Arrays are more compact vertically and seem nice for this job. Adding @{~\mapsto~} to the column specification also saves some typing and makes the code cleaner.

\documentclass{article}
\usepackage{amsmath}
\begin{document}

\begin{equation*}
  \left[
    \begin{array}{c @{~~\mapsto~~} c}
      o_1 & \left[\begin{array}{c @{~\mapsto~} c}
      o_1 & 1 \\
      o_2 & 0 \\
      o_3 & 0
    \end{array} \right] \\ [1.5em]
      o_2 & \left[\begin{array}{c @{~\mapsto~} c}
      o_1 & 1 \\
      o_2 & 1 \\
      o_3 & 0 \\
    \end{array} \right]\\ [1.5em]
      o_3 & \left[\begin{array}{c @{~\mapsto~} c}
      o_1 & 0 \\
      o_2 & 0 \\
      o_3 & 1
    \end{array} \right] \\   
    \end{array} 
  \right]
\end{equation*}

\end{document}

Brackets inside brackets with newline inside

3 Answers3