Dear Dick, > -----Original Message----- > From: Richard and Barbara Males [mailto:rbma...@gmail.com] > Sent: March-09-11 10:54 AM > To: John Fox > Cc: r-help@r-project.org > Subject: Re: [R] R Commander QQ Plot with triangular distribution > > 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"..
I don't see a way around this problem, short of something like writing cover functions yourself with different argument names, e.g., qtri <- function(p, A, B, C) qtriangle(p, a=A, b=B, c=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. No need to apologize -- this is a reasonable question and reveals a flaw in the interface to qqPlot(), and it's not obvious how to fix it. Suggestions would be appreciated. Best, John > > 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.
