Drop or add Z and/or M dimensions from feature geometries

Drop Z and/or M dimensions from feature geometries, resetting classes appropriately

st_zm(x, ..., drop = TRUE, what = "ZM")

Arguments

x	object of class sfg, sfc or sf
...	ignored
drop	logical; drop, or (FALSE) add?
what	character which dimensions to drop or add

Details

Only combinations drop=TRUE, what = "ZM", and drop=FALSE, what="Z" are supported so far. In case add=TRUE, x should have XY geometry, and zero values are added for Z.

Examples

st_zm(st_linestring(matrix(1:32,8)))
#> LINESTRING (1 9, 2 10, 3 11, 4 12, 5 13, 6 14, 7 15, 8 16)
x = st_sfc(st_linestring(matrix(1:32,8)), st_linestring(matrix(1:8,2)))
st_zm(x)
#> Geometry set for 2 features 
#> geometry type:  LINESTRING
#> dimension:      XY
#> bbox:           xmin: 1 ymin: 3 xmax: 8 ymax: 16
#> CRS:            NA
#> LINESTRING (1 9, 2 10, 3 11, 4 12, 5 13, 6 14, ...
#> LINESTRING (1 3, 2 4)
a = st_sf(a = 1:2, geom=x)
st_zm(a)
#> Simple feature collection with 2 features and 1 field
#> geometry type:  LINESTRING
#> dimension:      XY
#> bbox:           xmin: 1 ymin: 3 xmax: 8 ymax: 16
#> CRS:            NA
#>   a                           geom
#> 1 1 LINESTRING (1 9, 2 10, 3 11...
#> 2 2          LINESTRING (1 3, 2 4)