Nested Undersets

Question

how would you achieve something like this?

right now my code looks like this:

90\underset{+90}{\underset{\huge \smile}{\underset{+90}{\underset{\huge \smile}{}}180\underset{+180}{\underset{\huge \smile}{}}}}360\underset{+240}{\underset{\huge \smile}{}}600

The code itself is obviously a huge mess but it produces the output above, the problem is that I can't seem to get the second nested underset working, by that i mean the underset which is not in the figure from +180 to +240. Any ideas? Also, if you have a better way of doing this, please tell me :P

score 8 · Accepted Answer · answered Nov 29 '20 at 21:58

Here, I introduce

\bsmile[<under-depth-offset>]{<main-text>}{<underset-text>}

If #2 is blank, the width of the typeset is derived from the \smile...otherwise it is derived from the width of #2.

The MWE

\documentclass{article}
\usepackage{stackengine}
\newcommand\bsmile[3][0pt]{\if\relax#2\relax\def\tmp{F}\else\def\tmp{T}\fi
  \ensurestackMath{\stackengine{#1}{#2}{%
  \stackengine{1pt}{\mbox{\huge$\smile$}}{\scriptstyle#3}{U}{c}{F}{T}{S}}
  {U}{c}{F}{\tmp}{S}}}
\begin{document}
$90\bsmile{}{+90}\bsmile[16pt]{180}{+90}\bsmile{}{+180}360\bsmile{}{+240}600$
\end{document}

brilliant, thank you! – underset-nester Nov 29 '20 at 22:18 — underset-nester, Nov 29 '20 at 22:18

score 6 · Answer 2 · 2020-11-29T22:28:38.053

Here is a simple array.

\documentclass[fleqn]{article}
\usepackage{mathtools}
\usepackage{relsize}
\newcommand{\scriptclap}[1]{\mathclap{\scriptstyle #1}}
\newcommand{\LargerSmile}{\mathlarger{\mathlarger{\mathlarger{\mathlarger\smile}}}}
\begin{document}
Some text.
\[ \begin{array}[t]{*7{c@{}}}
 90 && 180 && 360 && 600\\[-1ex]
 & \LargerSmile & & \LargerSmile & & \LargerSmile &\\[-1ex]
 &\scriptclap{+90} & &\scriptclap{+180} && \scriptclap{+240}&\\[-1ex]
 & & \LargerSmile & & & &\\[-1ex]
 & & \scriptclap{+90} & & & &\\
\end{array} \quad\dots \text{more stuff} \]
More text.
\end{document}

The more stuff is just to show that you can align the top row with other parts of the formula. If this is not needed, remove [t] after \begin{array}.

For more complicated tasks I recommend TikZ with the tikzmark library.

that's a nice solution thank you very much – underset-nester Nov 29 '20 at 22:18 — underset-nester, Nov 29 '20 at 22:18

score 6 · Answer 3 · answered Nov 29 '20 at 22:27

With a not so complicated syntax:

\documentclass{article}
\usepackage{amsmath,array}
\newcommand{\differences}[1]{%
  \begingroup
  \def?##1{\hidewidth\scriptstyle\mathstrut##1\hidewidth\kern0pt}%
  \def\U{\mbox{\huge$\smile$}}%
  \settowidth{\dimen255}{\U}
  \renewcommand{\arraystretch}{0}%
  \setlength{\arraycolsep}{0pt}%
  \begin{array}{*{20}{w{c}{\dimen255}}}
  #1
  \end{array}%
  \endgroup
}
\begin{document}
[
\differences{
  90 && 180 && 360 && 600 \
  & \U && \U && \U  \
  & ?{+90} && ?{+180} && ?{+240} \
  && \U && \U \
  && ?{+90} && ?{+60} \
  &&& \U \
  &&& ?{+30}
}
]
[
\differences{
  640 && 231 && 100 && 91 && 1003 \
  & \U && \U && \U && \U \
  & ?{-409} && ?{-131} && ?{-9} && ?{+912} \
  && \U && \U && \U \
  && ?{+278} && ?{+122} && ?{921} \
  &&& \U && \U \
  &&& ?{-156} && ?{+799} \
  &&&& \U \
  &&&& ?{955}
}
]
\end{document}

No more than four digits in the main numbers.

Nested Undersets

3 Answers3