[texhax] Problem with eqnarray

[Robin Fairbairns]

>  	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.

in that case, you're not compiling what we see here, or you've some
highly eccentric package you don't bother to mention:

> \begin{eqnarray}
>   f(x,y,z) & = & P \times \\
>   \exp \left \[ -\left( \frac{ \cos \theta \cos \phi (x - \mu_x) \\

\[ opens displaymath mode, so \left\[ produces the error

  ! Missing delimiter (. inserted).

and then (if you're crazy enough to press on)

  ! LaTeX Error: Bad math environment delimiter.

>                             + \sin \theta (y - \mu_y) \\
>                    - \cos \theta \sin \phi (z - \mu_z)}{A_x} \right)^2 \\

i suggest you clear up that error (there's a \] later on to clear up,
too).  if that lot then works, perhaps you might consider using one of
the amsmath align environments in place of the seriously grotty
eqnarray