[Rd] R postscript generation error (lines versus points) (PR#5285)

[Peter Dalgaard]

Stephen.Harker at spme.monash.edu.au writes:

> Full_Name: Stephen Harker
> Version: 1.80
> OS: linux (Yellow Dog 3.0 on ppc)
> Submission from: (NULL) (130.194.13.101)
> 
> 
> In creating a postscript file from a set of data in which the points are
> plotted
> using `points()' and lines drawn using `lines()' I have found since upgrading
> from R version 1.4? to 1.8 that the two sets do not coinicide completely.  This
> is best illustrated by a simple example given below.  Here the X11() output
> appears correctly.  However, the postscript output shows that the lines and
> points no
> longer coincide on the right hand side, whereas the left hand side is perfect. 
> Output to other devices such as pdf is perfect.  Possibly this reflects a
> different scaling being applied when points() or lines() are selected. 
> 
> One reason I found this is that I use a number of scripts in R to plot and
> multiplot data sets from x-ray and neutron powder diffraction analysis (and
> Rietveld fitting of this data in particularl).  In these points() is used to
> plot the data and lines() to plot the refinement from the analysis.  After
> upgrading I found these were 
> misaligned.  The example was created to mimic the problem.
> 
> %%% Example follows:
> dtwoth <- seq(from=20,to=80,len=1024)
> dcount <- rnorm(dtwoth) #
> 
> postscript(file="R-test2.ps",horizontal=FALSE,
>          pointsize=18, onefile=FALSE,
>          family="Helvetica", paper="a4") 
> 
> plot(dtwoth,dcount, 
>   xlim=c(min(dtwoth),max(dtwoth)),ylim=c(min(dcount),max(dcount)),
>  yaxt="n",xaxs="i",yaxs="i",xlab="2theta",ylab="counts",
>  type="n")
> 
> lines(dtwoth,dcount)
> points(dtwoth,dcount)

[At the current rate, "1.80" would be about 36 years into the future.
Latest version is 1.8.1.]

I can't reproduce this with 1.8.0 on RedHat 8.0. Are you sure it isn't
your Postscript viewer that is playing tricks on you??

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
 (*) \(*) -- University of Copenhagen   Denmark      Ph: (+45) 35327918
~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk)             FAX: (+45) 35327907