[R] Long lines with Sweave

[Jan T. Kim]

On Wed, Sep 14, 2005 at 02:49:56PM +0200, Henrik Andersson wrote:
> Jan T. Kim wrote:
> > On Wed, Sep 14, 2005 at 10:14:59AM +0200, Henrik Andersson wrote:
> > 
> >>I have used Sweave a lot the latest year, but never really used any long 
> >>function calls.
> >>
> >>
> >>If I have code which look like this
> >>
> >>-------------------------------------------------------------
> >>gof <- benthic.flux(ID="Gulf of Finland",
> >>                     meas.conc=conc,
> >>                     bw.conc=bw.conc,
> >>                     time=times,
> >>                     substance=expression(DIC~(mmol~m^{-3}))
> >>                     )
> >>-------------------------------------------------------------
> >>
> >>I get the output by Sweave in my pdf file, like this:
> >>
> >>---------------------------------------------------------------
> >> > gof <- benthic.flux(ID = "Gulf of Finland", meas.conc = conc,
> >>+ bw.conc = bw.conc, time = times, substance = expression(DIC ~
> >>+ (mmol ~ m^{
> >>+ -3
> >>+ })))
> >>----------------------------------------------------------------
> >>
> >>I can understand that it will not look exactly as entered but why is the 
> >>'-3' on a line of it's own?
> >>
> >>Can anyone suggest a idea to how I can make this more readable.
> > 
> > 
> > It seems you've been thinking LaTeX rather than R ;-)  :
> > The exponent "-3" in the expression should be enclosed by parentheses
> > rather than by curly braces.
> > 
> > The code formatting done by the print method inserts the newline after
> > "{" and before "}".
> > 
> > Best regards, Jan
> 
> If you look at demo(plotmath), I get the impression that m^(-3) does not 
> give me the desired behavior.
> 
> I want to have -3 in superscript without visible parentheses.
> 
> Tricky!

Ok, I see.

It seems to me that you could omit the curly braces in the example, I
don't see any differences between the title in the plots produced by

    plot(1:10, main = expression(DIC~(mmol~m^-3)))

and

    plot(1:10, main = expression(DIC~(mmol~m^{-3})))

For more complex exponents, you could try plain() to prevent them from
being wrongly grouped by operator precedence, as in

    plot(1:10, main = expression(DIC~(mmol~m^plain(-3 + t))))

Not exactly ideal for readability, however...

Best regards, Jan
-- 
 +- Jan T. Kim -------------------------------------------------------+
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