hi folks, Bit of a newbie, but I've spent a fair bit of time looking for an answer on this, with no joy. Can anyone help me? Dataset: A single column of values in a csv file (eg. 52, 53, 54, 85, etc) Goal: In Minitab, you have what they call a dot plot. It's a histogram, where a single dot represents a set of identical values (eg. 57, 57, 57 would be one dot). Multiple dots are stacked on top of each other (as if gravity was affecting them). The advantage is that outliers are very visible (since a single 155 still gets a single dot). The net effect is a rug plot, but in the main portion of the plot, not just on the axis. Tried: I've played with dotchart and dotchart2 with no joy (eg. dotchart(nc$bac) (where nc is the dataset and bac is the column header). They do provide multiple dots (so that ten values of 57 are given 3 dots) but these overlap and aren't arranged in a logical way. Sometimes a single dot has a large y-value, sometimes it isn't. As a result of this non-gravitational effect, it doesn't look like a histogram at all. It's also strange that the background of the plot is stripy. This implies I'm doing something very wrong, but don't know what. I had a look at the plot galleries, and didn't see anything else that looked like what I wanted (except the rug plots). thanks! (and apologies if I've missed something blatant) Paul -- View this message in context: http://www.nabble.com/Dot-plot---equivalent-of-MINITAB-tp19677009p19677009.html Sent from the R help mailing list archive at Nabble.com.
I think the problem is that what you describe is not what some
people, R folks included, refer to as "dotplot", though I suppose
wikipedia as well as some other top google links seem to agree with
you and minitab. What you describe I think can be obtained with
something like:
x<- c(6,6,4,4,4,4,2,2,2,2,2,10)
cnt <- table(x)
xs <- rep(as.numeric(names(cnt)), cnt)
ys <- do.call("c", sapply(cnt, function(x) 1:x))
plot(xs,ys, pch=19, ylim=c(0,10))
The R-dotplot you can think of, if you want, as a replacement of a
barchart, which replaces the entire bar with a single dot where the
bar would end. It can also be used when the scale you are using has
nothing to do with counts, and doesn't even have to start from 0. But
I am far from an expert, and I am sure/hope a bunch of people will
jump in to correct me.
There are surely other descriptions of dotplots, but you could start
with these:
http://www.processtrends.com/pg_charts_dot_plots.htm
http://www.b-eye-network.com/view/2468
Haris Skiadas
Department of Mathematics and Computer Science
Hanover College
On Sep 25, 2008, at 3:51 PM, kerfuffle wrote:
>
> hi folks,
>
> Bit of a newbie, but I've spent a fair bit of time looking for an
> answer on
> this, with no joy. Can anyone help me?
>
> Dataset: A single column of values in a csv file (eg. 52, 53, 54,
> 85, etc)
>
> Goal: In Minitab, you have what they call a dot plot. It's a
> histogram,
> where a single dot represents a set of identical values (eg. 57,
> 57, 57
> would be one dot). Multiple dots are stacked on top of each other
> (as if
> gravity was affecting them). The advantage is that outliers are
> very visible
> (since a single 155 still gets a single dot). The net effect is a
> rug plot,
> but in the main portion of the plot, not just on the axis.
>
> Tried: I've played with dotchart and dotchart2 with no joy (eg.
> dotchart(nc$bac) (where nc is the dataset and bac is the column
> header).
> They do provide multiple dots (so that ten values of 57 are given 3
> dots)
> but these overlap and aren't arranged in a logical way. Sometimes
> a single
> dot has a large y-value, sometimes it isn't. As a result of this
> non-gravitational effect, it doesn't look like a histogram at all.
> It's
> also strange that the background of the plot is stripy. This
> implies I'm
> doing something very wrong, but don't know what. I had a look at
> the plot
> galleries, and didn't see anything else that looked like what I wanted
> (except the rug plots).
>
> thanks! (and apologies if I've missed something blatant)
>
> Paul
> --
> View this message in context: http://www.nabble.com/Dot-plot---
> equivalent-of-MINITAB-tp19677009p19677009.html
> Sent from the R help mailing list archive at Nabble.com.
>
>
On 26/09/2008, at 7:51 AM, kerfuffle wrote:> > hi folks, > > Bit of a newbie, but I've spent a fair bit of time looking for an > answer on > this, with no joy. Can anyone help me? > > Dataset: A single column of values in a csv file (eg. 52, 53, 54, > 85, etc) > > Goal: In Minitab, you have what they call a dot plot. It's a > histogram, > where a single dot represents a set of identical values (eg. 57, > 57, 57 > would be one dot). Multiple dots are stacked on top of each other > (as if > gravity was affecting them). The advantage is that outliers are > very visible > (since a single 155 still gets a single dot). The net effect is a > rug plot, > but in the main portion of the plot, not just on the axis. > > Tried: I've played with dotchart and dotchart2 with no joy (eg. > dotchart(nc$bac) (where nc is the dataset and bac is the column > header). > They do provide multiple dots (so that ten values of 57 are given 3 > dots) > but these overlap and aren't arranged in a logical way. Sometimes > a single > dot has a large y-value, sometimes it isn't. As a result of this > non-gravitational effect, it doesn't look like a histogram at all. > It's > also strange that the background of the plot is stripy. This > implies I'm > doing something very wrong, but don't know what. I had a look at > the plot > galleries, and didn't see anything else that looked like what I wanted > (except the rug plots).Here's something that will do at least roughly what you want. The fundamentals of this function were written for me by Barry Rowlingson. (Thanks Baz!) dotplot.mtb <- function (x, xlim = NULL, main = NULL, xlab = NULL, pch = 19, hist = FALSE, yaxis = FALSE) { if (is.null(xlim)) xlim <- range(pretty(range(x))) if (is.null(main)) main <- "" if (is.null(xlab)) xlab <- "" x <- sort(x) w <- table(x) mw <- max(w) w <- unlist(lapply(w, function(n) { 1:n })) Nmax <- floor(par()$pin[2]/strheight("o", units = "inches")) if (mw <= Nmax & !hist) { plot(range(x, na.rm = TRUE), c(0, 1), type = "n", xlab = "", ylab = "", xlim = xlim, main = main, axes = FALSE) par(usr = c(par()$usr[1:2], -Nmax/2, Nmax/2)) y <- strheight("o") * w points(x, y, pch = pch) axis(side = 1, pos = 0) if (yaxis) { a <- 0 b <- round(Nmax/10) at <- seq(a, by = b, length = 10) axis(side = 2, at = at) } } else { if (hist) plot(x, w, type = "h", xlab = "", ylab = "", xlim = xlim, ylim = c(-mw - 1, mw + 1), main = main, axes = FALSE) else plot(x, w, pch = pch, xlab = "", ylab = "", xlim = xlim, ylim = c(-mw - 1, mw + 1), main = main, axes = FALSE) axis(side = 1, pos = -0.02 * mw) if (yaxis) { a <- 0 b <- max(1, round(mw/10)) at <- seq(a, by = b, length = 10) axis(side = 2, at = at) } } } cheers, Rolf Turner ###################################################################### Attention:\ This e-mail message is privileged and confid...{{dropped:9}}
Paul, Have you tried the dotplot() function in the package epicalc? I think it does what you want. Sammy kerfuffle wrote:> > hi folks, > > Bit of a newbie, but I've spent a fair bit of time looking for an answer > on this, with no joy. Can anyone help me? > > Dataset: A single column of values in a csv file (eg. 52, 53, 54, 85, etc) > > Goal: In Minitab, you have what they call a dot plot. It's a histogram, > where a single dot represents a set of identical values (eg. 57, 57, 57 > would be one dot). Multiple dots are stacked on top of each other (as if > gravity was affecting them). The advantage is that outliers are very > visible (since a single 155 still gets a single dot). The net effect is a > rug plot, but in the main portion of the plot, not just on the axis. > > Tried: I've played with dotchart and dotchart2 with no joy (eg. > dotchart(nc$bac) (where nc is the dataset and bac is the column header). > They do provide multiple dots (so that ten values of 57 are given 3 dots) > but these overlap and aren't arranged in a logical way. Sometimes a > single dot has a large y-value, sometimes it isn't. As a result of this > non-gravitational effect, it doesn't look like a histogram at all. It's > also strange that the background of the plot is stripy. This implies I'm > doing something very wrong, but don't know what. I had a look at the plot > galleries, and didn't see anything else that looked like what I wanted > (except the rug plots). > > thanks! (and apologies if I've missed something blatant) > > Paul >----- Blay S KATH Kumasi, Ghana. -- View this message in context: http://www.nabble.com/Dot-plot---equivalent-of-MINITAB-tp19677009p19687574.html Sent from the R help mailing list archive at Nabble.com.
I suggest the panel.dotplot.tb in the HH package. It is a lattice panel function and therefore works with standard trellis formulas including conditioning variables and grouping variables. library(HH) example(panel.dotplot.tb) Since you define what you want in terms of Minitab, I mention that this is available in the Graphs menu with Rcmdr when you install the RcmdrPlugin.HH package. Rich