[pstricks] problem in equation numbering

[Herbert Voss]

On 18.04.2013 17:45, Kari Eloranta wrote:

> \info{{\blue Resistance}\\%
> The resistance of an electrical component is
> \begin{equation}
> R=\frac{V}{I}
> \end{equation}\label{eq:res}
> where $V$ is the potential difference across the component, and $I$ the electric current flowing through it.}
>
> the equation number (label) becomes 1.20 in the output pdf. However, when I try use \ref{eq:res} to reference the equation, the reference tag is 1.10 instead of 1.20. Recompiling does not help. Is there a solution to this problem?

try

\begin{equation}\label{eq:res}
R=\frac{V}{I}
\end{equation}

the label should be inside the environment.
if it doesn't help then provide a _complete_ example

Herbert