[O] Batch processing part of a file

[Loris Bennett]

Dear List,

I have an orgmode file for collecting data and producing a plot.  The
file contains a Perl script which runs on a remote machine and generates
Graphviz input.  This is then used to create a PDF file.

I have had a look at

  http://orgmode.org/manual/Batch-execution.html

but it is not clear to me how I would navigate to the right part of the
file so that I could then call org-babel-execute-src-block.

Can anyone help?

Thanks

Loris