R help - Mar 2016 - Typographical error in the documentation of function strwidth?

There might be a minor typographical error in the documentation of the function
strwidth, namely, from

?strwidth

we get:

"Note that the ?height? of a string is determined only by the number of
linefeeds ("\n") it contains: it is the (number of linefeeds - 1)
times the line spacing plus the height of "M" in the selected font.
(...)"

I think the correct phrasing should be:

"Note that the ?height? of a string is determined only by the number of
linefeeds ("\n") it contains: it is the (number of linefeeds) times
the line spacing plus the (number of linefeeds + 1) times the height of
"M" in the selected font. (...)"

Alberto Monteiro

I don't think so. I'll give you that it should either be the (number of
lines - 1)*spacing or (number of linefeeds)*spacing, but it's correct to
count the height of "M" only on the top line.

-pd

It is correct as written
> On 16 Mar 2016, at 22:39 , ALBERTO VIEIRA FERREIRA MONTEIRO <albmont at
centroin.com.br> wrote:
> 
> There might be a minor typographical error in the documentation of the
function strwidth, namely, from
> 
> ?strwidth
> 
> we get:
> 
> "Note that the ?height? of a string is determined only by the number
of linefeeds ("\n") it contains: it is the (number of linefeeds - 1)
times the line spacing plus the height of "M" in the selected font.
(...)"
> 
> I think the correct phrasing should be:
> 
> "Note that the ?height? of a string is determined only by the number
of linefeeds ("\n") it contains: it is the (number of linefeeds) times
the line spacing plus the (number of linefeeds + 1) times the height of
"M" in the selected font. (...)"
> 
> Alberto Monteiro
> 
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-- 
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Office: A 4.23
Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com

Peter Dalgaard wrote:
> I don't think so. I'll give you that it should either be the
(number of lines - 1)*spacing
> or (number of linefeeds)*spacing, but it's correct to count the height
of "M" only on the top line.
> 
> -pd
> 
> It is correct as written
> 
Ah, ok, I see now. The "line spacing" is not the line spacing, but the
inter-line spacing plus
the height of "M":

"Note that the ?height? of a string is determined only by the number of
linefeeds ("\n") it contains: it is the (number of linefeeds - 1)
times the line spacing plus the height of "M" in the selected font.
For an expression it is the height of the bounding box as computed by plotmath.
Thus in both cases it is an estimate of how far above the final baseline the
typeset object extends. (It may also extend below the baseline.) The inter-line
spacing is controlled by cex, par("lheight") and the ?point size? (but
not the actual font in use)"

It's still confusing... Specially since there's no way to get the
inter-line spacing except by running

strheight("M\nM") - 2 * strheight("M")

Alberto Monteiro