[R] diag() problem

[Robin Hankin]

Hi

I have a matrix "u", for which diag() gives an error:

u <- structure(c(5.42334674128216, -2.31319389204264, -5.83059042218476,
  -1.64112369640695, -2.31319389212801, 3.22737617646609,  
1.85200668021569,
  -0.57102273078531, -5.83059042231881, 1.85200668008156,  
11.9488923894962,
  -3.5525537165941, -1.64112369587405, -0.571022730886046,  
-3.55255371755604,
  10.0989829379577), .Dim = c(4, 4), .Dimnames = list(c("constant",
  NA, NA, NA), c("constant", NA, NA, NA)))

 > u
           constant       <NA>      <NA>       <NA>
constant  5.423347 -2.3131939 -5.830590 -1.6411237
<NA>     -2.313194  3.2273762  1.852007 -0.5710227
<NA>     -5.830590  1.8520067 11.948892 -3.5525537
<NA>     -1.641124 -0.5710227 -3.552554 10.0989829
 > is.matrix(u)
[1] TRUE
 > diag(u)
Error in if (is.list(nms) && !any(sapply(nms, is.null)) && all((nm <-  
nms[[1]][1:m]) ==  :
     missing value where TRUE/FALSE needed

 >


What's going on here?




 > R.version
          _
platform powerpc-apple-darwin8.2.0
arch     powerpc
os       darwin8.2.0
system   powerpc, darwin8.2.0
status
major    2
minor    2.0
year     2005
month    10
day      06
svn rev  35749
language R
 >




--
Robin Hankin
Uncertainty Analyst
National Oceanography Centre, Southampton
European Way, Southampton SO14 3ZH, UK
  tel  023-8059-7743