Turn off automatic size adjustment of \left and \right brackets

Question

I have used different left/right brackets (\left(, \left[, \left\{ etc.) in a document numerous time and realised only now (due to changes) that the automatic size adjustment that comes with these brackets/braces does not fit well and that I mostly want the “normal” size for all instead.

Is there a way to turn off this automatic size adjustment, such that for each brace the same (normal) size is used? I know I should, given my change of mind, probably replace each \left( by a plain (, but I am hoping for a quick (though possibly dirty) solution.

Answer 1

I don't recommend this really!

\left is actually a TeX command and has one argument being the delimiter. In this case, the delimiter should be typeset only,so the effect of \left is to be gobbled. (The same is for \right...)

As campa noted in his comment: \left... and \right... are important commands in amsmath and changing their definitions will not break for example matrix etc. resulting in an compilation error but it will break their visual appareance.

I've stored \left... and \right... for the pmatrix environment for example to show how to preserve the usual behaviour there!

\documentclass{article}

\usepackage{amsmath}
\usepackage{xpatch}

\let\origleft\left
\let\origright\right

% Save it for the pmatrix environment, for example
\xpatchcmd{\pmatrix}{\left(}{\origleft(}{}{}
\xpatchcmd{\endpmatrix}{\right)}{\origright)}{}{}




\begin{document}

Before

$\left(\left(a+b\right)^2\right)$

$\left[\left(a+b\right)^2\right]$

$\left\{\left(a+b\right)^2\right\}$

$\begin{pmatrix}
  a & b \\
  c & d \\
\end{pmatrix}$


Now redefining them:

\renewcommand{\left}[1]{%
#1
}
\renewcommand{\right}[1]{%
#1%
}

After:

$\left(\left(a+b\right)^2\right)$

$\left[\left(a+b\right)^2\right]$

$\left\{\left(a+b\right)^2\right\}$

$\begin{pmatrix}
  a & b \\
  c & d \\
\end{pmatrix}$



\end{document}