R help - Oct 2010 - Recovering x/y coordinates from a scatterplot image

Do I recall correctly that there is an R package that can take an image, 
and help one estimate the x/y coordinates?  I can't find the package, 
thought it was an R-tool, but would appreciate any leads.

Thanks,

Rob

On Fri, Oct 15, 2010 at 9:46 PM, Rob James <aetiologic at gmail.com>
wrote:
> Do I recall correctly that there is an R package that can take an image,
and
> help one estimate the x/y coordinates? ?I can't find the package,
thought it
> was an R-tool, but would appreciate any leads.
>
> Thanks,
 I dont know an R package for this, but there are various programs to
do it, none of which I can ever remember the name once every six years
when I need it. Some searching on the internet has found this one:

http://plotdigitizer.sourceforge.net/

but doubtless there are others!

Barry

Hi Rob:

Are you thinking of the digitize package?

HTH,
Dennis

On Fri, Oct 15, 2010 at 1:46 PM, Rob James <aetiologic@gmail.com> wrote:
> Do I recall correctly that there is an R package that can take an image,
> and help one estimate the x/y coordinates?  I can't find the package,
> thought it was an R-tool, but would appreciate any leads.
>
> Thanks,
>
> Rob
>
> ______________________________________________
> R-help@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.
>
	[[alternative HTML version deleted]]

You can do this by reading in the image and plotting it, then use the updateusr
function from the TeachingDemos package to set the user coordinates to match the
image (use locator to find the current values of some points).  Then you can
just use the locator function to get the coordinates of the points.

-- 
Gregory (Greg) L. Snow Ph.D.
Statistical Data Center
Intermountain Healthcare
greg.snow at imail.org
801.408.8111

> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of Rob James
> Sent: Friday, October 15, 2010 2:46 PM
> To: r-help at r-project.org
> Subject: [R] Recovering x/y coordinates from a scatterplot image
> 
> Do I recall correctly that there is an R package that can take an
> image,
> and help one estimate the x/y coordinates?  I can't find the package,
> thought it was an R-tool, but would appreciate any leads.
> 
> Thanks,
> 
> Rob
> 
> ______________________________________________
> 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.