[Rd] Historical NA question

Hervé Pagès hpages at fhcrc.org
Tue May 6 21:23:05 CEST 2014

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.


> 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 , Hervé Pagès <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
>> ______________________________________________
>> R-devel at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-devel

Hervé Pagès

Program in Computational Biology
Division of Public Health Sciences
Fred Hutchinson Cancer Research Center
1100 Fairview Ave. N, M1-B514
P.O. Box 19024
Seattle, WA 98109-1024

E-mail: hpages at fhcrc.org
Phone:  (206) 667-5791
Fax:    (206) 667-1319

More information about the R-devel mailing list