# case brackets too big? [duplicate]

document class: report

$f(x)= \begin{cases} 1 &\text{if } x\in U\\ F(x) &\text{if } x\notin U. \end{cases}$

If $T$ is open in $[0,1]$ then

$f^{-1}[T]=\begin{cases} \big(F^{-1}[T]\cap X\big)\cup U &\text{if } 1\in T\\ F^{-1}[T]\cap V &\text{if } 1\notin T, \end{cases}$


This produces

Does anyone else think the brackets look a little too big? How can I correct this?

EDIT: I believe the problem is that \doublespace is used throughout the document. (I was able to replicate the image using that). \linespread{1} made the brackets smaller, but it only seems to work if it's outside of the proof environment (and then it shrinks everything!).

• Do you have \renewcommand{\arraystretch}{<num>} somewhere in your preamble? – Werner Apr 6 '17 at 23:30
• @Werner no. it's a really big preamble (for my dissertation) but I did a search and didn't find it. – D.S. Lipham Apr 6 '17 at 23:31
• Please provide a complete but minimal code example. This makes it easier to help and shows some effort on your side. In the meantime you could have a look at tex.stackexchange.com/questions/240868 – Dr. Manuel Kuehner Apr 6 '17 at 23:33
• Okay. We need to be able to replicate the problem in order to address it. And, using your code snippet in a minimal example/document does not produce that output. You must be doing something other than the default in order to achieve that output, and it's currently anyone's guess. – Werner Apr 6 '17 at 23:36
• Remove parts of a copy of your document, starting all with text before and after the formula, and ending with each command of the preamble, until the problem disappear. Then undo the last change, check that the problem is still there and check again if remain code not related with the problem and not esssential to compile the file. Then post it the whole document, but probably you know now what is the problem. – Fran Apr 7 '17 at 1:44

The problem can be reproduced with package setspace and setting a larger line space, e.g. \doublespacing. Also the table like lines of environment cases are affected by the larger \baselineskip:

\documentclass{article}
\usepackage{amsmath}
\usepackage{setspace}
\doublespacing
\begin{document}
$f(x)= \begin{cases} 1 &\text{if } x\in U\\ F(x) &\text{if } x\notin U. \end{cases}$

If $T$ is open in $[0,1]$ then

$f^{-1}[T]=\begin{cases} \big(F^{-1}[T]\cap X\big)\cup U &\text{if } 1\in T\\ F^{-1}[T]\cap V &\text{if } 1\notin T, \end{cases}$
\end{document}


Environment singlespace switches back to normal spacing for the equations:

\documentclass{article}
\usepackage{amsmath}
\usepackage{setspace}
\doublespacing
\begin{document}
\begin{singlespace}
$f(x)= \begin{cases} 1 &\text{if } x\in U\\ F(x) &\text{if } x\notin U. \end{cases}$
\end{singlespace}

If $T$ is open in $[0,1]$ then

\begin{singlespace}
$f^{-1}[T]=\begin{cases} \big(F^{-1}[T]\cap X\big)\cup U &\text{if } 1\in T\\ F^{-1}[T]\cap V &\text{if } 1\notin T, \end{cases}$
\end{singlespace}
\end{document}


• aha! I didn't know you could use begin and end with singlespace – D.S. Lipham Apr 7 '17 at 2:25