Historical NA question
On May 6, 2014, at 1:06 PM, Herv? Pag?s wrote:
On 05/06/2014 12:36 PM, William Dunlap wrote:
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.
> els <- 2:1 > set <- 1:6 > - els%in%set
[1] FALSE FALSE
> - is.element(els,set)
[1] -1 -1
That is not demonstrating that " els%in%set gives a different result than is.element(els,set) ". It is again demonstrating that "-" has a higher precedence than '%in%'.
-(els%in%set)
[1] -1 -1
- is.element(els,set)
[1] -1 -1
David. > So following your advice doesn't really help me leave my precedence > problems behind. > > H. > >> 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 >>>>> >>>>> ______________________________________________ >>>>> R-devel at r-project.org mailing list >>>>> https://stat.ethz.ch/mailman/listinfo/r-devel >>> >>> >>> -- >>> Herv? Pag?s >>> >>> 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 > > -- > Herv? Pag?s > > 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 > > ______________________________________________ > R-devel at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel David Winsemius Alameda, CA, USA