[Rd] Historical NA question

[Hervé Pagès]

On 05/06/2014 01:15 PM, William Dunlap wrote:
> In your example els%in%set gave the same result as
> is.element(els,set), but because of precedence issues putting a unary
> minus in front caused them to be given different inputs - one got -els
> and the other got just els for the first argument.

So you confirm that to use your solution (i.e. replace my use of
'els%in%set' with 'is.element(els,set)') I need to think about
precedence?

> To change one to
> the other you have to edit the parsed expression, not the text.  If
> you used is.element in the first place you would avoid precedence
> issues.

"If you ... in the first place". Ahhhh, but that's not what I did. So
that doesn't help me.

H.

>  (I avoid creating %xxx% functions  because the precedence is
> not often what I want.)
> Bill Dunlap
> TIBCO Software
> wdunlap tibco.com
>
>
> On Tue, May 6, 2014 at 1:06 PM, Hervé Pagès <hpages at fhcrc.org> 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
>>
>> 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, Hervé Pagès <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 , 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
>>
>>
>> --
>> 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

-- 
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