Wow, quick response, works perfectly, just as needed. Thanks to both of you for pointing me in the right direction, and for your contributions to the R community.
Dick On Wed, Mar 9, 2011 at 11:21 AM, Peter Ehlers <ehl...@ucalgary.ca> wrote: > On 2011-03-09 07:53, Richard and Barbara Males wrote: >> >> Thank you for your prompt reply, I apologize for posting as an R >> Commander question. Your response is pointing me in the right >> direction, but I am still not quite there. The triangle package has >> a qtriangle and dtriangle. The formal arguments are a, b, and c. >> (formals(qtriangle)) When I use R Commander as: >> >> qqPlot(Transfer5000$Transfer.Rate, dist="triangle", a=3000,b=5000,c=4000) >> >> I get the error message: >> >> Error in qqPlot.default(Transfer5000$Transfer.Rate, dist = "triangle", : >> argument 5 matches multiple formal arguments >> >> and I am unclear as to how to specify that the "c" argument needs to >> pertain specifically to the qtriangle (or perhaps dtriangle) function >> arguments, that is, how to avoid a conflict with other arguments of >> qqPlot that are ambiguous when passed "c".. >> >> Again, sorry to post here, as this has clearly wandered into other >> territory. My exploratory searches to resolve this take me well >> beyond my current ability in R. If there is not an obvious answer, I >> will re-post specifically on the topic of specifying formal arguments >> of distributions to qqPlot. > > Dick, > > I think that the author of the triangle package has chosen > an unfortunate name for one of the parameters. Here's a > work-around: > > ## define two new functions dtri() and qtri(): > dtri <- function(q, a=0, b=1, cc=.5) dtriangle(q, a, b, cc) > qtri <- function(p, a=0, b=1, cc=.5) qtriangle(p, a, b, cc) > > ## now use "tri" as the distribution to pass to qqPlot: > qqPlot(x, "tri", a=3000, b=5000, cc=4000) > > Peter Ehlers > >> >> Thanks. >> >> Dick Males >> >> On Tue, Mar 8, 2011 at 11:19 AM, John Fox<j...@mcmaster.ca> wrote: >>> >>> Dear R. Males, >>> >>> This isn't really an R Commander question, since the qqPlot() function is >>> in >>> the car package and is just invoked by the R Commander. >>> >>> From ?qqPlot: "distribution: root name of comparison distribution - >>> e.g., >>> "norm" for the normal distribution ... Any distribution for which >>> quantile >>> and density functions exist in R (with prefixes q and d, respectively) >>> may >>> be used." Thus, if there's a qtriangle() and dtriangle(), I suppose that >>> you >>> should be able to get a QQ plot. Further from ?qqPlot: " ... arguments >>> such as df to be passed to the appropriate quantile function." Thus, you >>> should *name* the arguments to be passed to qtriangle() -- perhaps (of >>> course, you should use the correct names) min=3000, max=5000, mode=4000. >>> >>> I hope this helps, >>> John >>> >>> -------------------------------- >>> John Fox >>> Senator William McMaster >>> Professor of Social Statistics >>> Department of Sociology >>> McMaster University >>> Hamilton, Ontario, Canada >>> http://socserv.mcmaster.ca/jfox >>> >>> >>> >>> >>>> -----Original Message----- >>>> From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] >>>> On Behalf Of Richard and Barbara Males >>>> Sent: March-08-11 10:49 AM >>>> To: r-help@r-project.org >>>> Subject: [R] R Commander QQ Plot with triangular distribution >>>> >>>> I am attempting to use the R Commander Graphs Quantile-Comparison >>>> functionality on a dataset, to compare with a triangular distribution. >>>> I have the package triangle. My question is on the syntax of how >>>> to specify the parameters of the theoretical distribution in the >>>> Parameters field of the dialog box. For example, the theoretical >>>> distribution has min of 3000, max of 5000, mode of 4000. When I >>>> enter this info as 3000,5000,4000 in the parameters field, I get: >>>> >>>> qqPlot(EmpiricalData$Value, dist="triangle", 3000,5000,4000) >>>> >>>> it produces a plot, but I am not sure that this is correct. >>>> >>>> I have searched for examples, not found anything. Any help much >>>> appreciated. >>>> >>>> R. Males >>>> Cincinnati, Ohio, USA >>>> >>>> ______________________________________________ >>>> R-help@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. >>> >>> >> >> ______________________________________________ >> R-help@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. > > ______________________________________________ R-help@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.
