[R] how to specify the order of panels with xyplot

[Dan Kortschak]

> chromosomes
   id       refseq                       name    length
1   0  NC_000001.9  Homo sapiens chromosome 1 247249719
2   1 NC_000002.10  Homo sapiens chromosome 2 242951149
3   2 NC_000003.10  Homo sapiens chromosome 3 199501827
4   3 NC_000004.10  Homo sapiens chromosome 4 191273063
5   4  NC_000005.8  Homo sapiens chromosome 5 180857866
6   5 NC_000006.10  Homo sapiens chromosome 6 170899992
7   6 NC_000007.12  Homo sapiens chromosome 7 158821424
8   7  NC_000008.9  Homo sapiens chromosome 8 146274826
9   8 NC_000009.10  Homo sapiens chromosome 9 140273252
10  9  NC_000010.9 Homo sapiens chromosome 10 135374737
11 10  NC_000011.8 Homo sapiens chromosome 11 134452384
12 11 NC_000012.10 Homo sapiens chromosome 12 132349534
13 12  NC_000013.9 Homo sapiens chromosome 13 114142980
14 13  NC_000014.7 Homo sapiens chromosome 14 106368585
15 14  NC_000015.8 Homo sapiens chromosome 15 100338915
16 15  NC_000016.8 Homo sapiens chromosome 16  88827254
17 16  NC_000017.9 Homo sapiens chromosome 17  78774742
18 17  NC_000018.8 Homo sapiens chromosome 18  76117153
19 18  NC_000019.8 Homo sapiens chromosome 19  63811651
20 19  NC_000020.9 Homo sapiens chromosome 20  62435964
21 20  NC_000021.7 Homo sapiens chromosome 21  46944323
22 21  NC_000022.9 Homo sapiens chromosome 22  49691432
23 22  NC_001807.4 Homo sapiens mitochondrion     16571
24 23  NC_000023.9  Homo sapiens chromosome X 154913754
25 24  NC_000024.8  Homo sapiens chromosome Y  57772954
> xyplot(hits~bin|chromosomes$name[Chromosome+1],data=hits,horizontal=FALSE,origin=0,lab=c(3,10),pch=20,cex=0.01,layout=c(1,5,5),strip=strip.custom(style=3,bg="grey90",par.strip.text=list(cex=0.5)),as.table=TRUE)


I am wondering how to reorder the panels such that they are plotted in
the order of chromosomes$id rather than chromosomes$name. I am sure that
this has been answered in the past, but I am finding it difficult to
understand (I have looked at factor and reorder.factor).

(I've had a look at strip.custom to see if I can get what I want with
that, and it looks like I should be able to, but I can't figure out
how).

thanks
Dan