From: Deepayan Sarkar <deepayan.sarkar_at_gmail.com>

Date: Fri 17 Jun 2005 - 14:30:23 GMT

R-devel@r-project.org mailing list

https://stat.ethz.ch/mailman/listinfo/r-devel Received on Sat Jun 18 00:36:48 2005

Date: Fri 17 Jun 2005 - 14:30:23 GMT

On 6/17/05, Duncan Murdoch <murdoch@stats.uwo.ca> wrote:

> On 6/17/2005 8:58 AM, Deepayan Sarkar wrote:

*> > I think there are a couple of things in ?hist that are not quite as
**> > clear as they could be.
**> >
**> > (1)
**> >
**> > freq: logical; if 'TRUE', the histogram graphic is a representation
**> > of frequencies, the 'counts' component of the result; if
**> > 'FALSE', _relative_ frequencies ("probabilities"), component
**> > 'density', are plotted. Defaults to 'TRUE' _iff_ 'breaks'
**> > are equidistant (and 'probability' is not specified).
**> >
**> > Unless I'm missing something, the 'density' component is NOT relative
**> > frequency or 'probability' in any reasonable sense, country-specific
**> > biases notwithstanding, except in the very special case where
**> > all(diff(breaks) == 1). Thus, the above description is confusing and
**> > probably even wrong.
**>
**> I agree.
**>
**> > Also, it seems to me that hist cannot draw a relative frequency
**> > histogram at all (which is not a bad thing, but it's of course very
**> > important to the undergrads we're teaching intro stats and R to). This
**> > should be explicitly mentioned.
**>
**> I'm not sure about this. Is it really worth mentioning something if you
**> can't do it? Are you thinking of just giving a reference to barplot?
*

Not mentioning it is fine.

> > (2)

*> >
**> > breaks: one of:
**> >
**> > ...
**> > * a single number giving the number of cells for the
**> > histogram,
**> > ...
**> >
**> > This is not quite true. 'breaks' is used in 'pretty', so it's more a
**> > suggestion than an exact specification. I'm not sure whether or not
**> > the behaviour should be changed (what's the point of having ``pretty''
**> > breakpoints anyway?), but if not, the documentation should be
**> > clarified.
**>
**> I like the pretty breakpoints. It is good to label the breakpoints, and
**> ugly to have labels at other than pretty points. I'd clarify by
**> changing "giving" to "suggesting".
*

Actually, I missed the remark just below this:

In the last three cases the number is a suggestion only.

so this is fine as it is.

> > I'll be happy to provide a patch if these changes are considered reasonable.

*>
**> Please do.
*

Here's the output of svn diff. Is this a reasonable way of providing a patch?

Index: hist.Rd

- hist.Rd (revision 34748) +++ hist.Rd (working copy) @@ -28,9 +28,9 @@ } \item{freq}{logical; if \code{TRUE}, the histogram graphic is a representation of frequencies, the \code{counts} component of - the result; if \code{FALSE}, \emph{relative} frequencies - (\dQuote{probabilities}), component \code{density}, - are plotted. Defaults to \code{TRUE} \emph{iff} \code{breaks} are + the result; if \code{FALSE}, probability densities, component + \code{density}, are plotted (so that the histogram has a total area + of one). Defaults to \code{TRUE} \emph{iff} \code{breaks} are equidistant (and \code{probability} is not specified).} \item{probability}{an \emph{alias} for \code{!freq}, for S compatibility.} \item{include.lowest}{logical; if \code{TRUE}, an \code{x[i]} equal to

Deepayan

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https://stat.ethz.ch/mailman/listinfo/r-devel Received on Sat Jun 18 00:36:48 2005

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