# [texhax] Problem with eqnarray

Modhurita Mitra mmitra at astro.uiuc.edu
Fri Apr 8 09:30:49 CEST 2005

Hi,
I am having trouble compiling my file which contains an eqnarray.
At the third line in the following expression (the one beginning with
- \cos, I get an error.

\begin{eqnarray}
f(x,y,z) & = & P \times \\
\exp \left $-\left( \frac{ \cos \theta \cos \phi (x - \mu_x) \\ + \sin \theta (y - \mu_y) \\ - \cos \theta \sin \phi (z - \mu_z)}{A_x} \right)^2 \\ -\left(\frac{ \sin \theta \cos \phi (x - \mu_x) \\ + \cos \theta (y - \mu_y) \\ + \sin \theta \sin \phi (z - \mu_z)}{A_y} \right)^2 \\ -\left( \frac{\sin \phi (x - \mu_x) + \cos \phi (z - \mu_z)}{A_z} \right)^2 \right$ \\
\end{eqnarray}

The error message says:
! Missing } inserted.
<inserted text>
}
l.270 ...- \cos \theta \sin \phi (z - \mu_z)}{A_x}
\right)^2 \\
?
! Extra }, or forgotten \endgroup.
<inserted text> }

l.270 ...- \cos \theta \sin \phi (z - \mu_z)}{A_x}
\right)^2 \\
?
! Missing } inserted.
<inserted text>
}
l.270 ...- \cos \theta \sin \phi (z - \mu_z)}{A_x}
\right)^2 \\
?

I cannot find any unbalanced }'s. And it get stuck at this point in an
infinite loop, showing the same error again and again and doesn't compile
any further. What could be the source of error?

Thank you,
Sincerely,
Modhurita Mitra