Petr Savicky wrote: > Brian Ripley wrote: >> I wrote: >> > ## partial argument matching: >> > qbinom(p0 , s = 3, p = 0.25) ## 1 ??? >> > qbinom(p0-0.05, s = 3, p = 0.25) ## 1 ??? >> > qbinom(p0-0.06, s = 3, p = 0.25) ## 0 o.K. >> > >> > Unfortunately I have no I idea how to fix this. >> >> You use a call that specifies your intentions accurately. This is not >> 'partial argument matching': 'p' is an exact match to the first argument >> of >> >> > args(qbinom) >> function (p, size, prob, lower.tail = TRUE, log.p = FALSE) >> >> and that is how argument matching in R is documented to work. >> >> The 'inaccuracy' is in the diagnosis: please see the FAQ. > > Let me add an explanation, why > qbinom(p0 , s = 3, p = 0.25) > does not produce an error message about missing "prob" argument: > Since "size" and "p" arguments are given, p0 is used for > the third argument and not for the first. > > Although the behavior is logical, it may not be immediately clear. > I do not see this case explicitly in FAQ or R-intro.pdf 10.3.
To close this thread: First thanks to Brian and Petr for their explanation ---and to Petr for defending me. But I think, Brian was right, it was my fault not to see that qbinom's first argument 'p' was matched against my abbreviated 'prob' argument 0.25, which is ---I think--- the reason for Brian's "please see the FAQ"... Although not itself an FAQ nor in the R-intro manual, argument matching is completely & clearly described in http://cran.r-project.org/doc/manuals/R-lang.html#Argument-matching In fact my code is a badly chosen example: I am working on automatically generated q-, (and r,d,p)- functions, so left continuity of q<>-fct.'s is an issue. Unfortunately numbers p0 and .25 are so close together that they gave results only differing by 1 when interchanged, so I was led to the conclusion that it was a left-continuity-issue of qbinom with partial matched arguments which it was obviously not ---sorry for bothering you. As a conclusion which may be worth noting for other occasions as well: Be careful with partial argument matching ! Best, Peter ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
