Duncan, thank you for locating the problem. Martin, thank you for explaining the behavior and for the first pass at fixing it. With the fix, now the x-axis has ticks at all integers, and tick labels at c(-81,-67,-53,-39,-25,-11,0,9,19,31,43,55,67,79) This is with R-3.3.2, as I interpret your fix to be to only the R-intro.pdf manual with no change to the code of any of the functions. More work has to be done to repair the example.
I recommend plot(as.numeric(fr) ~ as.numeric(names(fr)), type="h", xlab="Determinant", ylab="Frequency") The slightly more obvious solution doesn't work > plot(fr ~ as.numeric(names(fr)), type="h", xlab="Determinant", > ylab="Frequency") Error in plot.table(c(-81, -80, -79, -78, -77, -76, -75, -74, -73, -72, : invalid table 'x' ## It is possible to change graphics:::Axis.table to if (is.num) axis(side, ...) ## and that would make the x-axis for the determinant example plot(fr, type="h", xlab="Determinant", ylab="Frequency") ## look sensible, but would ## be less appropriate for the following example. ## The current behavior of Axis.table makes sense in this example tt <- as.table(array(c(10,20,30), dimnames=list(c(100, 120, 200)))) tt plot(tt) On Mon, Jan 30, 2017 at 5:38 AM, Martin Maechler <maech...@stat.math.ethz.ch> wrote: >>>>>> Duncan Murdoch <murdoch.dun...@gmail.com> >>>>>> on Sun, 29 Jan 2017 06:32:27 -0500 writes: > > > On 29/01/2017 12:05 AM, Jim Lemon wrote: > >> Hi Richard, I think there may be something amiss in the > >> plot.table function. As you note, changing the class of > >> fr to array produces a more sensible plot, as does Bert's > >> "as.vector". Yet inside plot.table we find: > >> > >> plot(x0, unclass(x), ... > >> > >> and that should produce an array: > >> > >> class(unclass(fr)) [1] "array" > >> > >> The plot.table function looks like it should produce the > >> plot you want, but it doesn't. I think (therefore I am > >> probably wrong) that a 1D table is handled in the same > >> way as multiD table rather than being squeezed into a > >> vector. > > > I think the issue is that Axis() is called without > > removing the class. Axis.table sets ticks based on the > > names of the table. > > > Duncan Murdoch > > yes indeed! So this answers Rich Heiberger's question. > > The example stems from a time long before there was > a plot.table() method, and even longer before plot.default() had > started using Axis() and its methods. > > So a much nicer example for the R-intro -- committed a few > minutes ago -- is making use of the plot.table() S3 method : > > d <- outer(0:9, 0:9) > fr <- table(outer(d, d, "-")) > plot(fr, type="h", xlab="Determinant", ylab="Frequency") > > So this fulfills Rich's recommendation. > > Martin > > > >> On Sun, Jan 29, 2017 at 11:19 AM, Bert Gunter <bgunter.4...@gmail.com> > wrote: > >>> Rich: > >>> > >>> Simpler: Just lose the "table" class. > >>> > >>> plot(as.numeric(names(fr)), as.vector(fr), type="h", > >>> xlab="Determinant", ylab="Frequency") > >>> > >>> However, I'm no less puzzled by the "strange" behavior than you. > >>> > >>> In addition, it's probably worth noting that xyplot in lattice (and no > >>> doubt ggplot,too) does not have this problem (as I'm sure you know): > >>> > >>> xyplot(fr ~ as.numeric(names(fr)), type="h", > >>> xlab="Determinant", ylab="Frequency") > >>> > >>> > >>> Cheers, > >>> Bert > >>> Bert Gunter > >>> > >>> "The trouble with having an open mind is that people keep coming along > >>> and sticking things into it." > >>> -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) > >>> > >>> > >>> On Sat, Jan 28, 2017 at 3:03 PM, Richard M. Heiberger > <r...@temple.edu> wrote: > >>>> ## This example is from R-intro.pdf page 21 (R-3.3.2) > >>>> > >>>> d <- outer(0:9, 0:9) > >>>> fr <- table(outer(d, d, "-")) > >>>> plot(as.numeric(names(fr)), fr, type="h", > >>>> xlab="Determinant", ylab="Frequency") > >>>> ## The y-axis tick marks are at c(-21,24,65). > >>>> ## This seems to be because class(fr) == "table" > >>>> > >>>> ## Switching the class to array gives the more appropriate > >>>> ## y-axis ticks at seq(0,500,100) . > >>>> > >>>> fr.array <- fr > >>>> class(fr.array) <- "array" > >>>> plot(as.numeric(names(fr)), fr.array, type="h", > >>>> xlab="Determinant", ylab="Frequency") > >>>> > >>>> > >>>> ## I have a question and a recommendation. > >>>> ## Question: > >>>> ## Why are the y-axis ticks for the table defaulted to c(-21,24,65). > >>>> ## > >>>> ## Recommendation: > >>>> ## Changed the example on page 21 to show the ticks at > seq(0,500,100)? > >>>> > >>>> ## Rich > >>>> > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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 -- To UNSUBSCRIBE and more, see 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.
