Math & Science ⇒ Bracket size proble: Split multi-line equations

[denizkartan]

I have a long equation split into two lines and a large '(' bracket surrounding some parts of equation is also separated, i.e. \left( is in the upper line and \right) is in the lower line. In that case \left( resizes according to its contents but \right) doesn't resize and it is not even displayed. I am using AmsMath package and I know that it is better to use \Bigg commands, however even the largest \Bigg is much smaller than my equation's contents.

Code: Select all

\begin{align}
P &= some equation \\
&= \left( firstPart \\
   &{} + secondPart \right)
\end{align}

\left( displays big enough but \right) is not even displayed

[dnemoc]

Hi!

I know of a brute-force way of doing this, for instance:

Code: Select all

\begin{align*}
    \left( ---first line of the equation--- \right.\\
    \left. ---second line of the equation---\right)
\end{align*}

This works whenever the first and second lines have similar vertically-spaced stuff. For example, if the first line has a summation and the second line has only greek letters, then the `\right)' will appear a normal `)' and not a large one. I usually insert a \vphantom{\sum} in the second line somewhere between the `\left.' and `\right)' to get the parentheses to match each other.

Perhaps someone in this forum can suggest a cleaner way.

Best regards,
- D.

[Juanjo]

You can manually adjust the size of the delimiters, as shown here:

Code: Select all

\begin{align*}
    \Bigl( ---first line of the equation--- \\
           ---second line of the equation---\Bigr)
\end{align*}

Use one of the following pairs: \bigl-\bigr, \Bigl-\Bigr, \biggl-\biggr, \Biggl-\Biggr.

[jakob_s]

I had the same problem, but with more than just one bracket. I also tried to combine the {split}- to the {align}-environment, but it didn't work. So I used the \right. solution this time. But this problem will come back soon. So I would be glad about a solution without counting how many \right. I have put in. Anybody got an idea?

Best regards J

[phi]

have a look at the breqn package.

[martinvb]

The trick I've used makes use of a vertical placed underbrace. At this way you can specify a braces height manually. It took me a while to come up with a way, so hopefully this will be able to help somebody.

The code below produces a bracket of 1.5cm height.

Code: Select all

\usepackage{rotating}
\begin{sideways}\parbox{1.5cm}{$\underbrace{\hspace{1.5cm}}$}\end{sideways}

[mitesh_century]

use the \left and \right commands before the brackets..

here is an example:

Code: Select all

AC(T_i) = \left\{ S_i + h_i \sum_{j=R}^{R+T_i-1} (j-R) d_{ij}\right\}/T_i

[tekkerchrede]

You may also use the method of creating a phantom object as suggested at http://en.wikibooks.org/wiki/LaTeX/Adva ... formatting under "Braces spanning multiple lines".

[L Wolf]

You can manually adjust the size of the delimiters, as shown here:

Code: Select all

\begin{align*}
    \Bigl( ---first line of the equation--- \\
           ---second line of the equation---\Bigr)
\end{align*}

Use one of the following pairs: \bigl-\bigr, \Bigl-\Bigr, \biggl-\biggr, \Biggl-\Biggr.

Hi
I tried these synctaxes and it works! thank you so much

[Stefan Kottwitz]

Hi L Wolf,

welcome to the forum!

Maybe I can show you a way using breqn for automatic sizing braces spanning over lines if you would show us the formulas.

Stefan