On Mon, 30 Sep 2019, Rhys Dubin wrote:
Hi all,
I have a question regarding matrices (produced using poy2nb in spdep).
I’m trying to produce an adjacency matrix from a GIS Polygon shapefile
with about 500 individual polygons (queen or rook — it doesn’t really
matter for now), but conditional on the value of the parent polygon.
For instance, if a polygon had an arbitrary value of 1, I want to return
a list of all neighboring polygons that have a value of 2 or 3 (ie. ≠
1). The same would go for a polygon with a value of 2 (ie. return all
neighbors with a value of ≠ 2).
Is there a solution to this issue built into spdep, do I need to use a
different package, or is it possible to accomplish this with a
subsetting command?
No built-in solution, but to make progress a clear, reproducible example
is essential, otherwise we're guessing what you want. For example, add a
doctored variable to the eire or columbus data sets to show your needs. Do
you want a glist including (1) all neighbours j with a value of x not
equal to x[i], and excluding (0) all with x[j] == x[i]?
Roger
Thanks!
Rhys
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Roger Bivand
Department of Economics, Norwegian School of Economics,
Helleveien 30, N-5045 Bergen, Norway.
voice: +47 55 95 93 55; e-mail: roger.biv...@nhh.no
https://orcid.org/0000-0003-2392-6140
https://scholar.google.no/citations?user=AWeghB0AAAAJ&hl=en
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