Historical NA question

When does els%in%set give a different result than is.element(els,set)?
  I assumed they were copied form S+, where they are the same except
for argument names, but I may be wrong.

Bill Dunlap
TIBCO Software
wdunlap tibco.com


On Tue, May 6, 2014 at 12:23 PM, Herv? Pag?s <hpages at fhcrc.org> wrote:

On 05/06/2014 08:54 AM, William Dunlap wrote:

You can also use is.element(els,set) instead of the equivalent
els%in%set

No they are not *equivalent*. Equivalent means you could substitute
one by the other in your code without changing its behavior.

H.

and leave your precedence problems behind.
Bill Dunlap
TIBCO Software
wdunlap tibco.com


On Mon, May 5, 2014 at 10:35 PM, peter dalgaard <pdalgd at gmail.com> wrote:

On 06 May 2014, at 01:05 , Herv? Pag?s <hpages at fhcrc.org> wrote:

BTW, that %in% has precedence over arithmetic operations is surprising,
error-prone, and doesn't cover any reasonable use case (who needs to
multiply the logical vector returned by %in% by some value?) but that's
another story:

The point here is that the %foo% operators all have the _same_
precedence. In principle, they can be user-coded, and there is no way to
express what precedence is desirable. It may turn out slightly weird for
%in%, but think of what would happen if %*% had lower precedence than
addition.

--
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com

--
Herv? Pag?s

Program in Computational Biology
Division of Public Health Sciences
Fred Hutchinson Cancer Research Center
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