[R] "subscript out of range" message

[Thomas W Blackwell]

On Thu, 21 Aug 2003 arinbasu at softhome.net wrote:

> I was recently working with a dataset on arsenic poisoning. Among the
> variables in the dataset, I used the following three variables to produce
> crosstabulations (variable names: FOLSTAT, GENDER, ASBIN; all three were
> categorical variables, FOLSTAT denoted follow up status for the subjects and
> had seven levels, GENDER denoted sex (two levels: male,female), and ASBIN
> denoted binarized arsenic concentrations (two levels: "<0.05", ">0.05"
> denoting less than 0.05 mg/L and more than 0.05 mg/L respectively).
>
> To illustrate, I used the following code for crosstabulation:
>
> x <- table(FOLSTAT,GENDER,ASBIN)
>
> # from the results, I then wanted to subset a table for the ASBIN
> value ">0.05"
>
> I used the following code to subset the table:
>
> y <- x[,,ASBIN=">0.05"]
>
> # When I do this, R throws an error message stating "subscript out of
> range". However, it runs fine if I change the labels for my ASBIN variable
> from "<0.05" and ">=0.05" to words like "Nonexposed" and "Exposed"
> respectively.

I've tried to reproduce this behavior using R-1.7.1 on redhat 8.0 linux.
I can come close:  I can get an error message:  "subscript out of bounds",
not "out of range".  Seems to me that the variable name and equals sign
are ignored.  I can use any variable name I like, even ones that aren't
in my workspace.  Seems that matching is done by position in the string
of commas, not by the variable name, and I can only get the error message
"subscript out of bounds" when I've goofed up the matching by position -
for example, when I try to subscript the third dimension using a string
value from  dimnames(x)[[2]]  or  dimnames(x)[[1]].

Please try this again and see whether all the commas are there for
matching by position.  I think R ignores the presence of "ASBIN="
in your example above.

-  tom blackwell  -  u michigan medical school  -  ann arbor  -


> I searched the archives and the documentations for this, but could not find
> a solution. I understand that sometimes it is more expressive to use
> expressions like "<0.05" (or something similar) as headings in
> cross-tabulations. What was I doing incorrectly?
>
> Would greatly appreciate your insight.
>
> I use:
> R version: 1.7.1
> OS: Windows XP Home
>
> TIA,
> Arin Basu
>