[R] contour() & contourLines()

[(Ted Harding)]

Hi Peter!
Many thanks -- I had overlooked that line.
Ted.

On 22-Oct-09 18:53:25, Peter Ehlers wrote:
> Hi Ted,
> 
> Here's what the last example in ?contour says:
> 
>   "## contourLines produces the same contour lines as contour"
> 
> So, even without digging into the source, I would guess
> that your hunch is correct.
> 
> Cheers,
> Peter Ehlers
> 
> (Ted Harding) wrote:
>> Hi Folks,
>> I have been using contour() to produce some contour plots
>> (of a spatially-smooted density produced by kde2d()), with
>> very satisfactory results.
>> 
>> I now want access to the coordinates of the points on the
>> contours, and it would seem that contour() does not return a
>> value, so there is nothing from which these could be extracted.
>> 
>> However, apparently contourLines() does, and it seems to be
>> invoked in essentially the same way (so far as the x,y,z
>> and levels parameters are concerned).
>> 
>> However, I am not sure whether the contour lines generated
>> by contourLines() are the same numerically as those generated
>> (at any rate plotted) by contour().
>> 
>> By over-plotting the coordinates from contourLines() on the
>> contours plotted by contour(), it looks as though they may be
>> the same.
>> 
>> Advice would be appreciated!
>> With thanks,
>> Ted.
>> 
>> --------------------------------------------------------------------
>> E-Mail: (Ted Harding) <Ted.Harding at manchester.ac.uk>
>> Fax-to-email: +44 (0)870 094 0861
>> Date: 22-Oct-09                                       Time: 19:03:37
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>> 
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>> 
>>
> 
> ______________________________________________
> 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.

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E-Mail: (Ted Harding) <Ted.Harding at manchester.ac.uk>
Fax-to-email: +44 (0)870 094 0861
Date: 22-Oct-09                                       Time: 20:00:02
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