Message-ID: <alpine.LFD.2.02.1101271003460.10048@gannet.stats.ox.ac.uk>
Date: 2011-01-27T10:05:02Z
From: Brian Ripley
Subject: Increasing grayscale value in scatter plot with number of points on particular location
In-Reply-To: <AANLkTinkBubAS9hyuXKv-SGJjAbs_eVW5E0u=VHGHZ9w@mail.gmail.com>
On Thu, 27 Jan 2011, Aditya Bhagwat wrote:
> Dear Prof. Ripley,
>
> Thanks for your reply.
>
> This is one of the main points of supporting semi-transparent
> colours.
> You haven't told us your platform or graphics device (see the
> posting guide), but plotting with something like
> col=rgb(0,0,0,0.2) may work.
>
>
> I am working on Ubuntu Linux. and I tried the suggested approach but got an
> empty plot and the following warning message:
> In plot.xy(xy, type, ...) :
> ? semi-transparency is not supported on this device: reported only once per
> page
>
> Any suggestions on how to proceed?
Use a device that supports transparency: X11() ought to on a Linux
box, pdf() does everywhere.
>
> Many thanks,
>
> Aditya
>
>
>
>
> On Thu, 27 Jan 2011, Aditya Bhagwat wrote:
>
> Dear all,
>
> When making a plot with the command plot(xVector, yVector),
> there are many
> points that collide on the same place in the plot. In order to
> make this
> plot clearer, I have been looking for a way to colour the points
> based on
> the number of points that fall onto each other. If only one
> point falls on a
> particular location, make it gray, if many points fall, make it
> black.
>
> I tried to search the help archives, but didn't find any useful
> answers.
> Anyone has any suggestion?
>
> Many thanks for your help!
>
> Aditya
>
> --
> Aditya Bhagwat
>
> ? ? ? ?[[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible
> code.
>
>
> --
> Brian D. Ripley, ? ? ? ? ? ? ? ? ?ripley at stats.ox.ac.uk
> Professor of Applied Statistics, ?http://www.stats.ox.ac.uk/~ripley/
> University of Oxford, ? ? ? ? ? ? Tel: ?+44 1865 272861 (self)
> 1 South Parks Road, ? ? ? ? ? ? ? ? ? ? +44 1865 272866 (PA)
> Oxford OX1 3TG, UK ? ? ? ? ? ? ? ?Fax: ?+44 1865 272595
>
>
>
>
> --
> Aditya Bhagwat
>
>
>
>
--
Brian D. Ripley, ripley at stats.ox.ac.uk
Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel: +44 1865 272861 (self)
1 South Parks Road, +44 1865 272866 (PA)
Oxford OX1 3TG, UK Fax: +44 1865 272595