Error(s) in re-building vignettes:
  ...
--- re-building ‘SigTree.Rnw’ using Sweave
Found more than one class "Annotated" in cache; using the first, from namespace 'RNeXML'
Also defined by ‘S4Vectors’
Found more than one class "Annotated" in cache; using the first, from namespace 'RNeXML'
Also defined by ‘S4Vectors’
Found more than one class "Annotated" in cache; using the first, from namespace 'RNeXML'
Also defined by ‘S4Vectors’
Found more than one class "Annotated" in cache; using the first, from namespace 'RNeXML'
Also defined by ‘S4Vectors’
Found more than one class "Annotated" in cache; using the first, from namespace 'RNeXML'
Also defined by ‘S4Vectors’
Found more than one class "Annotated" in cache; using the first, from namespace 'RNeXML'
Also defined by ‘S4Vectors’
Error: processing vignette 'SigTree.Rnw' failed with diagnostics:
Running 'texi2dvi' on 'SigTree.tex' failed.
LaTeX errors:
! Paragraph ended before \@tempa was complete.
<to be read again> 
                   \par 
l.135 
      
! Paragraph ended before \@tempa was complete.
<to be read again> 
                   \par 
l.225 
      
! Paragraph ended before \@tempa was complete.
<to be read again> 
                   \par 
l.277 
      
! Paragraph ended before \@tempa was complete.
<to be read again> 
                   \par 
l.321 
      
! Paragraph ended before \@tempa was complete.
<to be read again> 
                   \par 
l.372 
      
! Paragraph ended before \@tempa was complete.
<to be read again> 
                   \par 
l.408 
      
! Paragraph ended before \@tempa was complete.
<to be read again> 
                   \par 
l.430 
      
! Paragraph ended before \@tempa was complete.
<to be read again> 
                   \par 
l.524 
      
! Paragraph ended before \@tempa was complete.
<to be read again> 
                   \par 
l.557 
      
! LaTeX Error: \begin{center} on input line 521 ended by \end{document}.

See the LaTeX manual or LaTeX Companion for explanation.
Type  H <return>  for immediate help.
 ...                                              
--- failed re-building ‘SigTree.Rnw’

SUMMARY: processing the following file failed:
  ‘SigTree.Rnw’

Error: Vignette re-building failed.
Execution halted