Displaying 3 results from an estimated 3 matches for "isocontour".
2003 Jun 16
2
Isocontour-lines of spatial data on a rectangular grid (not plots!)
Dear R-Listers,
I have spatial data on an equidistant rectangular grid, similar to
topographic data. I know that there are quite a few R-packages or base
functions that provide nice iso-contours plot, but I don't want a plot, just
the smoothed isocontour line of ONE level (e.g. 10 mm).
Data sets are large, so it would be preferable if the availability of
regular grid data could be exploited, and the fact that I only need ONE
isocontour line. Polynomial fits are not adequate, but loess works nicely
for the plots. Akima/interp might be a little too...
2013 Nov 08
1
how to derive true surface area from `computeContour3d' (misc3d package) -- follow up
...maximum of the array. so I believed that the
rendered cube actually
is the "outer surface" of the defined object in the example provided in
the manpage.
I know understandt it's an absolute level and `example(computeContour3d)'
consequently displays
some "interior" isocontour. this explains all my apparent errors.
I believe the manpage would benefit from a slight clarification that
`level' actually is
an absolute, not a relative/fractional threshold.
apologies for the noise.
j.
ps: it of course would still be nice, if the surface area (or a vector
containing...
2003 Jun 18
3
finding contours in a matrix
Hi,
I have matrix of sea bottom depths that I am plotting in R with the function
'image'.
I am particularly interested in the 200m depth contour (I'm using 'distance
from this feature' as a covariate in a model) and would like to extract the
data at evenly
spaced points along it. I can easily superimpose a line at 200m using the
function 'contour'. What I
want to