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R version 3.6.2 (2019-12-12) -- "Dark and Stormy Night"
Copyright (C) 2019 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)
R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.
R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.
Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.
> suppressPackageStartupMessages(library(sf))
> library(testthat)
> # "vertical" conversions:
> # column 1:
> mp = st_sfc(st_multipoint(matrix(0:3,,2)), st_multipoint(matrix(10:15,,2)))
> (ls = st_cast(mp, "LINESTRING"))
Geometry set for 2 features
geometry type: LINESTRING
dimension: XY
bbox: xmin: 0 ymin: 2 xmax: 12 ymax: 15
CRS: NA
LINESTRING (0 2, 1 3)
LINESTRING (10 13, 11 14, 12 15)
> st_cast(ls, "MULTIPOINT")
Geometry set for 2 features
geometry type: MULTIPOINT
dimension: XY
bbox: xmin: 0 ymin: 2 xmax: 12 ymax: 15
CRS: NA
MULTIPOINT ((0 2), (1 3))
MULTIPOINT ((10 13), (11 14), (12 15))
>
> # column 2:
> mls = st_sfc(st_multilinestring(list(rbind(c(0,0), c(10,0), c(10,10), c(0,10)),
+ rbind(c(5,5),c(5,6), c(6,6), c(6,5)))),
+ st_multilinestring(list(rbind(c(0,0), c(1,0), c(1,1), c(0,1)))))
> (pol = st_cast(mls, "POLYGON"))
Geometry set for 2 features
geometry type: POLYGON
dimension: XY
bbox: xmin: 0 ymin: 0 xmax: 10 ymax: 10
CRS: NA
POLYGON ((0 0, 10 0, 10 10, 0 10, 0 0), (5 5, 5...
POLYGON ((0 0, 1 0, 1 1, 0 1, 0 0))
> st_cast(pol, "MULTILINESTRING")
Geometry set for 2 features
geometry type: MULTILINESTRING
dimension: XY
bbox: xmin: 0 ymin: 0 xmax: 10 ymax: 10
CRS: NA
MULTILINESTRING ((0 0, 10 0, 10 10, 0 10, 0 0),...
MULTILINESTRING ((0 0, 1 0, 1 1, 0 1, 0 0))
>
> # "horizontal" conversions:
>
> (pt = st_cast(mp, "POINT"))
Geometry set for 5 features
geometry type: POINT
dimension: XY
bbox: xmin: 0 ymin: 2 xmax: 12 ymax: 15
CRS: NA
POINT (0 2)
POINT (1 3)
POINT (10 13)
POINT (11 14)
POINT (12 15)
> (i = attr(pt, "ids"))
[1] 2 3
> (xx = st_cast(pt, "MULTIPOINT", rep(seq_along(i), i)))
Geometry set for 5 features
geometry type: MULTIPOINT
dimension: XY
bbox: xmin: 0 ymin: 2 xmax: 12 ymax: 15
CRS: NA
MULTIPOINT ((0 2))
MULTIPOINT ((1 3))
MULTIPOINT ((10 13))
MULTIPOINT ((11 14))
MULTIPOINT ((12 15))
> (yy = st_cast(pt, "LINESTRING", rep(seq_along(i), i)))
Geometry set for 5 features
geometry type: LINESTRING
dimension: XY
bbox: xmin: 0 ymin: 2 xmax: 12 ymax: 15
CRS: NA
LINESTRING (0 2)
LINESTRING (1 3)
LINESTRING (10 13)
LINESTRING (11 14)
LINESTRING (12 15)
>
> (zz = st_cast(yy, "MULTILINESTRING"))
Geometry set for 5 features
geometry type: MULTILINESTRING
dimension: XY
bbox: xmin: 0 ymin: 2 xmax: 12 ymax: 15
CRS: NA
MULTILINESTRING ((0 2))
MULTILINESTRING ((1 3))
MULTILINESTRING ((10 13))
MULTILINESTRING ((11 14))
MULTILINESTRING ((12 15))
> #(zz = st_cast(yy, "POLYGON"))
>
> st_cast(mls, "LINESTRING")
Geometry set for 3 features
geometry type: LINESTRING
dimension: XY
bbox: xmin: 0 ymin: 0 xmax: 10 ymax: 10
CRS: NA
LINESTRING (0 0, 10 0, 10 10, 0 10)
LINESTRING (5 5, 5 6, 6 6, 6 5)
LINESTRING (0 0, 1 0, 1 1, 0 1)
>
> (g = st_sfc(c(mls, ls)))
Geometry set for 4 features
geometry type: GEOMETRY
dimension: XY
bbox: xmin: 0 ymin: 0 xmax: 12 ymax: 15
CRS: NA
MULTILINESTRING ((0 0, 10 0, 10 10, 0 10), (5 5...
MULTILINESTRING ((0 0, 1 0, 1 1, 0 1))
LINESTRING (0 2, 1 3)
LINESTRING (10 13, 11 14, 12 15)
> st_cast(g, "MULTILINESTRING")
Geometry set for 4 features
geometry type: MULTILINESTRING
dimension: XY
bbox: xmin: 0 ymin: 0 xmax: 12 ymax: 15
CRS: NA
MULTILINESTRING ((0 0, 10 0, 10 10, 0 10), (5 5...
MULTILINESTRING ((0 0, 1 0, 1 1, 0 1))
MULTILINESTRING ((0 2, 1 3))
MULTILINESTRING ((10 13, 11 14, 12 15))
> expect_warning(st_cast(g, "LINESTRING"))
> st_cast(st_cast(g, "MULTILINESTRING"), "LINESTRING") # will not loose
Geometry set for 5 features
geometry type: LINESTRING
dimension: XY
bbox: xmin: 0 ymin: 0 xmax: 12 ymax: 15
CRS: NA
LINESTRING (0 0, 10 0, 10 10, 0 10)
LINESTRING (5 5, 5 6, 6 6, 6 5)
LINESTRING (0 0, 1 0, 1 1, 0 1)
LINESTRING (0 2, 1 3)
LINESTRING (10 13, 11 14, 12 15)
>
> gc = st_sfc(st_geometrycollection(
+ list(
+ st_multilinestring(list(rbind(c(0,0), c(10,0), c(10,10), c(0,10)),
+ rbind(c(5,5),c(5,6), c(6,6), c(6,5)))),
+ st_multilinestring(list(rbind(c(0,0), c(1,0), c(1,1), c(0,1)))),
+ st_point(0:1)
+ )))
> try(st_cast(mls, "POINT"))
Geometry set for 12 features
geometry type: POINT
dimension: XY
bbox: xmin: 0 ymin: 0 xmax: 10 ymax: 10
CRS: NA
First 5 geometries:
POINT (0 0)
POINT (10 0)
POINT (10 10)
POINT (0 10)
POINT (5 5)
> try(st_cast(mls, "MULTIPOINT"))
Geometry set for 3 features
geometry type: MULTIPOINT
dimension: XY
bbox: xmin: 0 ymin: 0 xmax: 10 ymax: 10
CRS: NA
MULTIPOINT ((0 0), (10 0), (10 10), (0 10))
MULTIPOINT ((5 5), (5 6), (6 6), (6 5))
MULTIPOINT ((0 0), (1 0), (1 1), (0 1))
>
> outer = matrix(c(0,0,10,0,10,10,0,10,0,0),ncol=2, byrow=TRUE)
> hole1 = matrix(c(1,1,1,2,2,2,2,1,1,1),ncol=2, byrow=TRUE)
> hole2 = matrix(c(5,5,5,6,6,6,6,5,5,5),ncol=2, byrow=TRUE)
> pol1 = list(outer, hole1, hole2)
> pol2 = list(outer + 12, hole1 + 12)
> pol3 = list(outer + 24)
> mp = list(pol1,pol2,pol3)
> mp1 = st_multipolygon(mp)
> s = st_sfc(mp1)
> x = st_cast(s, "MULTIPOINT")
> x = st_cast(s, "POINT")
> expect_warning(st_cast(mp1, "LINESTRING"))
> expect_warning(st_cast(mp1, "POINT"))
> mls = mls[[1]]
> class(mls)
[1] "XY" "MULTILINESTRING" "sfg"
> #expect_error(st_cast(mls, "POLYGON"))
> st_cast(mls, "POLYGON")
POLYGON ((0 0, 10 0, 10 10, 0 10, 0 0), (5 5, 5 6, 6 6, 6 5, 5 5))
>
> expect_warning(st_cast(mls, "POINT"))
> p1 = st_polygon(pol1)
> expect_warning(st_cast(p1, "POINT"))
> ls = ls[[1]]
> class(ls)
[1] "XY" "LINESTRING" "sfg"
> expect_warning(st_cast(ls, "POINT"))
>
> mls = st_cast(p1, "MULTILINESTRING")
> p2 = st_cast(mls, "POLYGON")
>
> # st_is:
> st_is(st_point(0:1), "POINT")
[1] TRUE
> sfc = st_sfc(st_point(0:1), st_linestring(matrix(1:6,,2)))
> st_is(sfc, "POINT")
[1] TRUE FALSE
> st_is(sfc, "POLYGON")
[1] FALSE FALSE
> st_is(sfc, "LINESTRING")
[1] FALSE TRUE
> st_is(st_sf(a = 1:2, sfc), "LINESTRING")
[1] FALSE TRUE
> st_is(sfc, c("POINT", "LINESTRING"))
[1] TRUE TRUE
>
> #1194:
> wkt <- "MULTICURVE (COMPOUNDCURVE (LINESTRING (-83.62333 35.55244, -83.62328 35.55232, -83.62323 35.55223, -83.62319 35.55216, -83.62312 35.55209, -83.6231 35.55207), CIRCULARSTRING (-83.6231 35.55207, -83.62307 35.55205, -83.62302 35.55204), LINESTRING (-83.62302 35.55204, -83.62299 35.55203, -83.62289 35.55198, -83.62281 35.55189, -83.62271 35.55182)))"
> g <- st_as_sfc(wkt)
> g <- st_sf(demo = "test", geom = g, crs = 4326)
> m = st_cast(g, "MULTILINESTRING")
> identical(m$geom[[1]], st_cast(g$geom[[1]], "MULTILINESTRING"))
[1] TRUE
>
> proc.time()
user system elapsed
0.358 0.052 0.400
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