[Rd] Problem with points/lines (PR#10472)

Peter Dalgaard P.Dalgaard at biostat.ku.dk
Fri Nov 30 10:24:29 CET 2007


Gavin Simpson wrote:
> On Thu, 2007-11-29 at 17:34 +0100, Peter Dalgaard wrote:
>   
>> Gavin Simpson wrote:
>>     
>>> On Thu, 2007-11-29 at 16:36 +0100, Peter Dalgaard wrote:
>>>   
>>>       
>>>> carlos at necsi.org wrote:
>>>>     
>>>>         
>>>>> Full_Name: Carlos Gershenson
>>>>> Version: 2.6.1
>>>>> OS: MacOSX
>>>>> Submission from: (NULL) (24.128.48.138)
>>>>>
>>>>>
>>>>> Hi,
>>>>>
>>>>> Try this out:
>>>>>
>>>>> x<-1:10
>>>>> y<-x/2
>>>>> plot(table(x))
>>>>> points(table(y))
>>>>> #or lines(table(y))
>>>>>
>>>>> No matter what's the value of y, it prints out in the coordinates of x... this
>>>>> happens only with tables, not with simple plot(x), points(y), and table(y) works
>>>>> fine
>>>>>
>>>>>   
>>>>>       
>>>>>           
>>>> The real issue is that we have a plot method for tables, which tries to
>>>> be smart about using numerical entry names. There's no similar points
>>>> method, nor a lines method, so in those cases you get the default
>>>> method, namely to plot the table values (all ones) against the *index*,
>>>> i.e.,1:n. This shows the effect quite clearly:
>>>>
>>>> plot(table(x^2)
>>>> lines(table(x))
>>>>
>>>> (This is not a bug, since noone has promised you that lines and point
>>>> methods should exist. It could be taken as an enhancement request.)
>>>>     
>>>>         
>>> Peter,
>>>
>>> Re: your final statement above, would an enhancement request be looked
>>> upon favourably by R Core for inclusion in R if some code and
>>> documentation were supplied?
>>>   
>>>       
>> As always, there is a risk that it falls through the cracks before
>> someone gets around to looking at it.
>>
>> Your code look sane though, and as far as I can see, you do not even
>> have to do much in terms of documentation since it could be wedged into
>> the existing plot.table() help page.
>>
>> For now, we could file under "wishlist". As you know, items on the
>> wishlist do in fact get fulfilled sometimes.
>>
>>     -p
>>     
>
> OK. I'll prepare a patch against the R development SVN for the Rd file
> and take another look at the code I wrote. Can you refile this bug under
> "wishlist" or do I need to submit another bug report to achieve this?
>   
It's been moved there already by someone ( who also attached a comment
which may sound harsher than meant...)

    -p
> All the best,
>
> G
>
>   
>>> I replied earlier in the week to Carlos' query on R-Help (seems this has
>>> taken 2 days to get the R-Devel?) with some quickly knocked together
>>> code for points.table and Axis.table methods that were based in large
>>> part on the code in plot.table. I reproduce these below. They were based
>>> on printing the source plot.table at the prompt, not from interrogation
>>> of the SVN version.
>>>
>>> If considered for inclusion, I'd be happy to get these in better shape
>>> and write appropriate Rd files as required?
>>>
>>> All the best,
>>>
>>> G
>>>
>>> ## points and Axis methods for objects of class "table"
>>> ## Gavin Simpson 2007 based in large part on plot.table
>>> `points.table` <- function (x, type = "h", ...)
>>> {
>>>      rnk <- length(dim(x))
>>>      if (rnk == 0)
>>>          stop("invalid table 'x'")
>>>      if (rnk == 1) {
>>>          nx <- dimnames(x)[[1]]
>>>          ow <- options(warn = -1)
>>>          is.num <- !any(is.na(xx <- as.numeric(nx)))
>>>          options(ow)
>>>          x0 <- if (is.num)
>>>              xx
>>>          else seq.int(x)
>>>          points(x0, unclass(x), type = type, ...)
>>>      }
>>>      else stop("only for 1-D table")
>>> }
>>>
>>> `Axis.table` <- function(x, at, ..., labels)
>>> {
>>>      rnk <- length(dim(x))
>>>      if (rnk == 0)
>>>          stop("invalid table 'x'")
>>>      if (rnk == 1) {
>>>          nx <- dimnames(x)[[1]]
>>>          ow <- options(warn = -1)
>>>          is.num <- !any(is.na(xx <- as.numeric(nx)))
>>>          options(ow)
>>>          x0 <- if (is.num)
>>>              xx
>>>          else seq.int(x)
>>>          if(missing(at))
>>>              at <- x0
>>>          if(missing(labels))
>>>              labels <- nx
>>>          xaxt <- if (length(as <- list(...))) {
>>>              if (!is.null(as$axes) && !as$axes)
>>>                  "n"
>>>              else as$xaxt
>>>          }
>>>          axis(1, at = at, labels = labels, xaxt = xaxt)
>>>      }
>>>      else stop("only for 1-D table")
>>> }
>>>
>>> ## example to run with:
>>> set.seed(1234)
>>> x <- sample(1:10, 30, replace = TRUE)
>>> y <- x / 2
>>> plot(table(x), type = "p")
>>> points(table(y), col = "red", type = "p", pch = 2)
>>>
>>> ## And if you need to redraw axes
>>> ## need to use Axis() as it is a generic version of axis()
>>> plot(table(x), type = "p", axes = FALSE)
>>> points(table(y), col = "red", type = "p", pch = 2)
>>> Axis(table(y))
>>>
>>>   
>>>       
>> -- 
>>    O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
>>   c/ /'_ --- Dept. of Biostatistics     PO Box 2099, 1014 Cph. K
>>  (*) \(*) -- University of Copenhagen   Denmark          Ph:  (+45) 35327918
>> ~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk)                  FAX: (+45) 35327907
>>
>>
>>     


-- 
   O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
  c/ /'_ --- Dept. of Biostatistics     PO Box 2099, 1014 Cph. K
 (*) \(*) -- University of Copenhagen   Denmark          Ph:  (+45) 35327918
~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk)                  FAX: (+45) 35327907



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