Keep only rows in shp that lie on the border between two administrative
units and have at least one adjacency connection across that border.
seam_geom(adj, shp, admin, seam, epsg = 3857)subset of shp containing only rows on the selected seam
data('rockland')
data('orange')
data('nrcsd')
o_and_r <- rbind(orange, rockland)
o_and_r <- o_and_r |>
geo_filter(nrcsd) |>
geo_trim(nrcsd)
adj <- adjacency(o_and_r)
seam_geom(adj, shp = o_and_r, admin = 'county', seam = c('071', '087'))
#> Simple feature collection with 24 features and 25 fields
#> Geometry type: GEOMETRY
#> Dimension: XY
#> Bounding box: xmin: -8247177 ymin: 5049265 xmax: -8235418 ymax: 5060742
#> Projected CRS: WGS 84 / Pseudo-Mercator
#> First 10 features:
#> state county tract block GEOID waterpct pop pop_white pop_black
#> 486 36 071 013800 3031 360710138003031 0 0 0 0
#> 660 36 071 013800 3066 360710138003066 0 0 0 0
#> 668 36 071 013800 3045 360710138003045 0 0 0 0
#> 937 36 071 013900 3113 360710139003113 0 0 0 0
#> 2478 36 071 013800 3032 360710138003032 0 0 0 0
#> 4278 36 071 013900 3108 360710139003108 0 0 0 0
#> 4448 36 071 014900 1091 360710149001091 0 0 0 0
#> 5332 36 071 013800 3036 360710138003036 1 0 0 0
#> 5334 36 071 013800 3044 360710138003044 1 0 0 0
#> 5533 36 071 013800 3043 360710138003043 1 0 0 0
#> pop_hisp pop_aian pop_asian pop_nhpi pop_other pop_two vap vap_white
#> 486 0 0 0 0 0 0 0 0
#> 660 0 0 0 0 0 0 0 0
#> 668 0 0 0 0 0 0 0 0
#> 937 0 0 0 0 0 0 0 0
#> 2478 0 0 0 0 0 0 0 0
#> 4278 0 0 0 0 0 0 0 0
#> 4448 0 0 0 0 0 0 0 0
#> 5332 0 0 0 0 0 0 0 0
#> 5334 0 0 0 0 0 0 0 0
#> 5533 0 0 0 0 0 0 0 0
#> vap_black vap_hisp vap_aian vap_asian vap_nhpi vap_other vap_two place
#> 486 0 0 0 0 0 0 0 99999
#> 660 0 0 0 0 0 0 0 99999
#> 668 0 0 0 0 0 0 0 99999
#> 937 0 0 0 0 0 0 0 82750
#> 2478 0 0 0 0 0 0 0 99999
#> 4278 0 0 0 0 0 0 0 82750
#> 4448 0 0 0 0 0 0 0 99999
#> 5332 0 0 0 0 0 0 0 99999
#> 5334 0 0 0 0 0 0 0 99999
#> 5533 0 0 0 0 0 0 0 99999
#> geometry
#> 486 MULTIPOLYGON (((-8237395 50...
#> 660 MULTIPOLYGON (((-8238303 50...
#> 668 MULTIPOLYGON (((-8238234 50...
#> 937 MULTIPOLYGON (((-8241105 50...
#> 2478 MULTIPOLYGON (((-8237787 50...
#> 4278 MULTIPOLYGON (((-8241634 50...
#> 4448 MULTIPOLYGON (((-8247157 50...
#> 5332 MULTIPOLYGON (((-8236666 50...
#> 5334 MULTIPOLYGON (((-8236121 50...
#> 5533 MULTIPOLYGON (((-8236047 50...