Including TikZ picture in Sweave gets me an overfull box error

Question

I have some difficulties in R Sweave so I hope someone could help me.

I want to include two TikZ pictures using minipage and figure to the R Sweave but I get an error:

Overfull \hbox (2.43085pt too wide). 

The code I'm using is (I have deleted some rows because the code is too long):

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{arrows}
\begin{document}
\begin{figure}[!ht]  
\begin{minipage}[c]{0.5\linewidth}  
\centering  
\begin{tikzpicture}[>=triangle 45, scale=0.85]  
  \draw[line width=0.2mm] (-0.25,-0.25)--(-0.25,4.5)--(6.25,4.5)--(6.25,-0.25)--(-0.25,-0.25);  
\end{tikzpicture}  
\end{minipage}  
\begin{minipage}[c]{0.5\linewidth}  
\centering  
\begin{tikzpicture}[>=triangle 45, scale=0.85]  
  \draw[line width=0.2mm] (-0.25,-0.25)--(-0.25,4.5)--(6.25,4.5)--(6.25,-0.25)--(-0.25,-0.25);  
\end{tikzpicture}  
\end{minipage}  
\caption{Picture}  
\label{fig:pic1}  
\end{figure}
\end{document}

On page How do you effectively debug overfull \hbox warnings? that if include I found that \showboxdepth=\maxdimen will tell what the real problem is. But this also shows the same error as before.

So my question is: Why do I get an error? What wrong with my code?

Answer 1

As noted in the initial comment the error is

\end{minipage}
\begin{minipage}[c]{0.5\linewidth}  

which should be

\end{minipage}%
\begin{minipage}[c]{0.5\linewidth}  

As you can not fit two .5\linewidth minipages and an inter-word space on to a single line.