[R] Lattice: Setting Conditioning Panel Order in Trellis Plots

[Rich Shepard]

   I've looked in Deepayan Sarkar's book without finding how to specify the
order of conditioning panels in a trellis plot. Here's the issue I'm trying
to resolve:

   Sampling locations along a stream channel are not sequentially numbered.
For example, the panel order for one plot (lower left to upper right, 4
panels per row): SC, SC-1, SC-100, SC-139, SC-140, SC-141, SC-145. SC-2,
SC-3, and SC-50. This is normal collation order, while I need numeric order.

   Is there a way for me to specify the panel order so the display is SC,
SC-1, SC-2, SC-3, SC-50, SC-100, SC-139, SC-140, SC-141, SC-145? If so,
please teach me how to do this.

Rich