[R] Page eject and clearing the console

[Bert Gunter]

Perhaps merely rephrasing David's comments,

"page" is not a meaningful physical entity -- it depends on font size,
line spacing, etc. and the physical "size" of the output surface,
which has no meaning for an "infinitely" (or at least up to tyhe
screen buffer's limit) scrollable screen viewing area.

But maybe David's "scroll" function is what you had in mind.

-- Bert

On Tue, Jan 4, 2011 at 10:55 AM, David Winsemius <dwinsemius at comcast.net> wrote:
>
> On Jan 4, 2011, at 1:27 PM, David Winsemius wrote:
>
>>
>> On Jan 4, 2011, at 1:19 PM, John Sorkin wrote:
>>
>>> I have received help on one of my questions (thank you Henrique Jorge
>>> and ), viz. how I can clear the console from an R program.
>>> I have not yet received help on how I can skip to the top of the next
>>> page, i.e. cat("\n") skips to the next line, is there an equivalent way
>>> to skip to the top of the next page?
>>
>> "\n" does NOT "skip to the next line". It is a character and it is
>> interpreted by some sort of program, say a a plotting program or a
>> word-processor as a line feed. You need to specify what sort of program you
>> intend to do this "skipping-to-next-page" action and also provide the
>> character sequence that that program uses to signal that action. (There are
>> not any pages in R except perhaps multi-page plots but you seem to be in
>> character mode at the moment.)
>>
>
> It has occurred to me that you may be asking for something that will give
> the illusion of "clearing the screen" but will in fact be just "printing" a
> page of blank space on a console display, scrolling would ahve been the name
> I would have given it. In which case:
>
> scroll <- function(lines=40) cat(rep("\n", lines))
> scroll()
>
>> --
>> David.
>>
>>
>>> Thanks,
>>> John
>>>
>>>
>>>
>>>
>>> John David Sorkin M.D., Ph.D.
>>> Chief, Biostatistics and Informatics
>>> University of Maryland School of Medicine Division of Gerontology
>>> Baltimore VA Medical Center
>>> 10 North Greene Street
>>> GRECC (BT/18/GR)
>>> Baltimore, MD 21201-1524
>>> (Phone) 410-605-7119
>>> (Fax) 410-605-7913 (Please call phone number above prior to faxing)>>>
>>> Henrique Dallazuanna <wwwhsd at gmail.com> 1/4/2011 11:58 AM >>>
>>> Take a look on:
>>> http://tolstoy.newcastle.edu.au/R/e11/help/10/09/8463.html
>>>
>>> On Tue, Jan 4, 2011 at 2:54 PM, John Sorkin
>>> <jsorkin at grecc.umaryland.edu>wrote:
>>>
>>>> (1) I know that \n when used in cat, e.g. cat("\n") produces a line
>>>
>>> feed
>>>>
>>>> (i.e. skips to the next line). Is there any escape sequence that will
>>>
>>> go to
>>>>
>>>> the top of the next page?
>>>> (2) I know that control L will clear the console. Is there an
>>>
>>> equivalent
>>>>
>>>> function or other means that can be used in R code to clear the
>>>
>>> console?
>>>>
>>>> Thanks,
>>>> John
>>>>
>>>>
>>>> John David Sorkin M.D., Ph.D.
>>>> Chief, Biostatistics and Informatics
>>>> University of Maryland School of Medicine Division of Gerontology
>>>> Baltimore VA Medical Center
>>>> 10 North Greene Street
>>>> GRECC (BT/18/GR)
>>>> Baltimore, MD 21201-1524
>>>> (Phone) 410-605-7119
>>>> (Fax) 410-605-7913 (Please call phone number above prior to faxing)
>>>>
>>>> Confidentiality Statement:
>>>> This email message, including any attachments, is for\...{{dropped:25}}
>>>
>>> ______________________________________________
>>> R-help at r-project.org mailing list
>>> https://stat.ethz.ch/mailman/listinfo/r-help
>>> PLEASE do read the posting guide
>>> http://www.R-project.org/posting-guide.html
>>> and provide commented, minimal, self-contained, reproducible code.
>>
>> David Winsemius, MD
>> West Hartford, CT
>>
>> ______________________________________________
>> R-help at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide
>> http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>
> David Winsemius, MD
> West Hartford, CT
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>



-- 
Bert Gunter
Genentech Nonclinical Biostatistics