Re: [R] plotting image/contour on irregular grid

From: roger koenker <>
Date: Sat 07 May 2005 - 06:39:00 EST

On May 6, 2005, at 2:45 PM, Roger Bivand wrote:

> On Fri, 6 May 2005, m p wrote:
>> Hello,
>> I'd like to make a z(x,y) plot for irregularly spaced
>> x,y. What are routines are available in R for this
>> purpose?
> One possibility is to interpolate a regular grid using interp() in the
> akima package, then use image() or contour(). Another is to use
> levelplot() with formula z ~ x + y in the lattice package, and the
> equivalent contourplot(); here, the x,y pairs must lie on a grid,
> but do
> not need to fill the grid (so are regularly spaced with missing grid
> cells).

You could also try tripack and rgl.triangles to produce piecewise linear surfaces on the Delaunay triangulation of the x,y points.

Roger mailing list PLEASE do read the posting guide! Received on Sat May 07 07:21:57 2005

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