\begin{Schunk}
\begin{Sinput}
 focalValues <- data.frame(x1 = c(1, 2, 3, 4), x2 = c(100,200))
 mAndM <- expand.grid(focalValues)
 mAndM[1:8, ]
\end{Sinput}
\begin{Soutput}
  x1  x2
1  1 100
2  2 100
3  3 100
4  4 100
5  1 200
6  2 200
7  3 200
8  4 200
\end{Soutput}
\end{Schunk}
