# Styling long equations - is there any convention ?

I was wondering if there is any convention for styling long mathematical equation ? I have an exuation which originaly took more than a pagewidth so I splited it using

eqnarray


however I think it still doesn't look good - the equation number is overlaping (a bit) with actual equation - it looks quite ugly. Is there any better way to format this equation

 \begin{eqnarray*}
\left( R_{j}p_{ij}^* \right)^T  \left( \frac{\partial R_{j} }{\partial \phi_{j}}p_{ij}^* \right)
& = &   \left( p_{ij}^* \right)^T
\left(
\begin{array}{cc}
\cos{\phi_{j}} & \sin{\phi_{j}} \\
-\sin{\phi_{j}} & \cos{\phi_{j}}
\end{array}
\right)
\left(
\begin{array}{cc}
-\sin{\phi_{j}} & -\cos{\phi_{j}} \\
\cos{\phi_{j}} & -\sin{\phi_{j}}
\end{array} \right)
p_{ij}^*
\\ & = & \left( p_{ij}^* \right)^T
\left(
\begin{array}{cc}
0 & -1 \\
1 & 0
\end{array}\right) p_{ij}^* = 0
\end{eqnarray*}


any suggestion would be great :) EDIT It seems to be a problem with rendering equations

-

It's strongly recommended to use align instead of eqnarray, besides more consistent spacing this also fixes the overlapping issue (of course align* and eqnarray*, as in the question, don't use numbering). For align*, load the amsmath package and have a look at the amsmath user's guide, which shows further environments for multiline equations with different alignment.

Your code can easily be modified this way:

\usepackage{amsmath}
...
\begin{align*}
\left( R_{j}p_{ij}^* \right)^T  \left( \frac{\partial R_{j} }{\partial
\phi_{j}}p_{ij}^* \right)
&=    \left( p_{ij}^* \right)^T
\left(
\begin{array}{cc}
\cos{\phi_{j}} & \sin{\phi_{j}} \\
-\sin{\phi_{j}} & \cos{\phi_{j}}
\end{array}
\right)
\left(
\begin{array}{cc}
-\sin{\phi_{j}} & -\cos{\phi_{j}} \\
\cos{\phi_{j}} & -\sin{\phi_{j}}
\end{array} \right)
p_{ij}^*\\
&= \left( p_{ij}^* \right)^T
\left(
\begin{array}{cc}
0 & -1 \\
1 & 0
\end{array}\right) p_{ij}^* = 0
\end{align*}

-