[R] contour algorithm

[Duncan Murdoch]

On 12-04-21 9:21 PM, Stoch astic wrote:
> First time user, so sorry if I don't understand protocol.. Anyway, I have
> created a data frame consisting of pearson's R values at various x and y
> coordinates and then plotted this using filled.contour. My data is similar
> to fMRI data except that it is a surface map reconstructed from
> histological sections. I like the results but would like to know how
> contours were detected. Google search provides me various sources claiming
> the algorithm used is undocumented. For example:
>
>
> http://wipaed.wiso.uni-goettingen.de/~holdenb1/R/library/base/html/contour.html
> "Draws contour lines for the desired levels. There is currently no
> documentation about the algorithm. The source code is in
> `$RHOME/src/main/plot.c'."

That's a very old copy of the help page.  You're generally better off 
using the ones installed with R, or the ones on CRAN 
(cran.r-project.org/web/packages) rather than what Google finds somewhere.

Duncan Murdoch

>
>
> Does anyone know where or how I can find the method by which contours are
> calculated?
>
> 	[[alternative HTML version deleted]]
>
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