[R] Subsetting a matrix

[(Ted Harding)]

On 14-Jul-03 Adelchi Azzalini wrote:
>> Maybe it is reasonable to propose incorporating "drop" as one of the
>> things you can set with "options"? :--
>> [...]
> 
> Perhaps this is a way-out. As usual, everything is feasible when we
> resort entirely on our own code.  The danger is that we might make
> use of some package (may be written some years ago) which assumes
> drop=TRUE is the default behaviour, and changing the default behaviour
> might (potentially) have disasterous effects.

Indeed. However, it should be OK when embarking on a block or function
of matrix computations, written by oneself, to enclose it between

  options(drop=FALSE)
  ...
  options(drop=TRUE)

(unless some of the standard or "base" matrix functions which one
might use in "..." depend on the default. How could one tell?).

Best wishes,
Ted.


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Date: 14-Jul-03                                       Time: 13:50:35
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