[R] (no subject)
jasont at indigoindustrial.co.nz
Wed Feb 25 02:27:21 CET 2004
> Some functions create objects for which extractor functions are written
> to pull out some partial result.
> I wish to extract partial results from functions without extractor
> for example, to pass a vector of results to another function.
There isn't a general solution to this problem - it's like saying "I'd
like to remove a part from my car engine that doesn't require a special
tool. How do I do this?"
> Specifically, how would I extract just the contingency table from
The command str() is your friend for finding how in particular to approach
a problem. See ?str, then try:
> zz <- ftable(Titanic)
ftable [1:16, 1:2] 0 118 0 4 0 154 0 13 35 387 ...
- attr(*, "row.vars")=List of 3
..$ Class: chr [1:4] "1st" "2nd" "3rd" "Crew"
..$ Sex : chr [1:2] "Male" "Female"
..$ Age : chr [1:2] "Child" "Adult"
- attr(*, "col.vars")=List of 1
..$ Survived: chr [1:2] "No" "Yes"
- attr(*, "class")= chr "ftable"
This tells you that the ftable object is a matrix-like structure: [1:16,
1:2] with row and column name attributes. To strip the attributes, I'd
coerce to a matrix (in this case).
> I'm new at programming in R.
> Even after looking at V&R S Programming I don't see a general approach.
Get V&R "Modern Applied Statistics with S". It's more what you need to
learn R/S. "S Programming" is for when you start seriously programming
(as opposed to using) R/S. It's not a beginning book at all.
Hope that helps
More information about the R-help