Math & Science ⇒ Sligthly larger parenthesis ?

[Cham]

I want to write something inside some parenthesis, but I'm having troubles with the parenthesis size. Of course, I tried the standard commands : \left( \right), \big( \big), \bigg( \bigg), \Big( \Big, but the results aren't satisfying.

More specifically, consider this example :

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f(x(t))

Currently, the exterior parenthesis are too small.

If I use this :

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f\left( x(t) \right)

the exterior parenthesis are of the same size as the interior parenthesis (I don't see any difference with the previous code)

If I use this instead :

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f\big( x(t) \big)

the exterior parenthesis are now too big.

Is there a way to define some slightly larger parenthesis than the normal ( ) ?

[Stefan Kottwitz]

Hi Cham,

it depends on the available font sizes. You can try it. The original definition of \big is:

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\def\big#1{{\hbox{$\left#1\vbox to8.5\p@{}\right.\n@space$}}}

Instead of 8.5pt, \Big uses 11.5pt, \bigg 14.5pt and \Bigg 17.5pt. You can define your own commands choosing different values, such as

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\makeatletter
\newcommand*{\bigs}[1]{{\hbox{$\left#1\vbox to8\p@{}\right.\n@space$}}}
\makeatother

It may look similar though. Raise the value step by step, until you can see a change. However, it might be the same symbol size like with \big.

Stefan

[Cham]

It doesn't make any difference : I'm getting the same parenthesis as normal, or as "\big". I need something in between.

[Stefan Kottwitz]

Hi Cham,

it seems that there's no symbol available of a size between. However, you could use \scalebox of the graphicx package, such as:

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\newcommand*{\bigs}[1]{\scalebox{1.07}{\ensuremath#1}}

A complete minimal working example:

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\documentclass[a4paper,12pt]{article}
\usepackage{amsmath,amssymb}
\usepackage{graphicx}
\newcommand*{\bigs}[1]{\scalebox{1.07}{\ensuremath#1}}
\begin{document}
$\big(f\bigs(x(t)\bigs)\big)$
\end{document}

scaled_parentheses.png (3.85 KiB) Viewed 9700 times

Stefan

[Cham]

This command is working. However, I'm not getting exactly what you have shown on the picture above: the new parenthesis aren't well centered on the default parenthesis. The new ones are slightly above (vertical offset).

Is there a way to make them perfectly aligned with the default parenthesis ?

[Stefan Kottwitz]

You could use \vcenter:

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\newcommand*{\bigs}[1]{\vcenter{\hbox{\scalebox{1.07}{\ensuremath#1}}}}

Stefan

[Cham]

Works great ! Thanks a lot for your precious help !