if (FALSE) {
# From a numeric vector of length 2, making a point type
topojson_json(c(-99.74, 32.45), pretty = TRUE)
topojson_json(c(-99.74, 32.45), type = "GeometryCollection")
## polygon type
### this requires numeric class input, so inputting a list will dispatch on the list method
poly <- c(
c(-114.345703125, 39.436192999314095),
c(-114.345703125, 43.45291889355468),
c(-106.61132812499999, 43.45291889355468),
c(-106.61132812499999, 39.436192999314095),
c(-114.345703125, 39.436192999314095)
)
topojson_json(poly, geometry = "polygon", pretty = TRUE)
# Lists
## From a list of numeric vectors to a polygon
vecs <- list(c(100.0, 0.0), c(101.0, 0.0), c(101.0, 1.0), c(100.0, 1.0), c(100.0, 0.0))
topojson_json(vecs, geometry = "polygon", pretty = TRUE)
## from a named list
mylist <- list(
list(latitude = 30, longitude = 120, marker = "red"),
list(latitude = 30, longitude = 130, marker = "blue")
)
topojson_json(mylist, lat = "latitude", lon = "longitude")
# From a data.frame to points
topojson_json(us_cities[1:2, ], lat = "lat", lon = "long", pretty = TRUE)
topojson_json(us_cities[1:2, ],
lat = "lat", lon = "long",
type = "GeometryCollection", pretty = TRUE
)
# from data.frame to polygons
head(states)
## make list for input to e.g., rMaps
topojson_json(states[1:351, ], lat = "lat", lon = "long", geometry = "polygon", group = "group")
# from a geo_list
a <- geojson_list(us_cities[1:2, ], lat = "lat", lon = "long")
topojson_json(a)
# sp classes
## From SpatialPolygons class
library("sp")
poly1 <- Polygons(list(Polygon(cbind(
c(-100, -90, -85, -100),
c(40, 50, 45, 40)
))), "1")
poly2 <- Polygons(list(Polygon(cbind(
c(-90, -80, -75, -90),
c(30, 40, 35, 30)
))), "2")
sp_poly <- SpatialPolygons(list(poly1, poly2), 1:2)
topojson_json(sp_poly)
topojson_json(sp_poly, pretty = TRUE)
## data.frame to geojson
geojson_write(us_cities[1:2, ], lat = "lat", lon = "long") %>% as.json()
# From SpatialPoints class
x <- c(1, 2, 3, 4, 5)
y <- c(3, 2, 5, 1, 4)
s <- SpatialPoints(cbind(x, y))
topojson_json(s)
## From SpatialPointsDataFrame class
s <- SpatialPointsDataFrame(cbind(x, y), mtcars[1:5, ])
topojson_json(s)
## From SpatialLines class
library("sp")
c1 <- cbind(c(1, 2, 3), c(3, 2, 2))
c2 <- cbind(c1[, 1] + .05, c1[, 2] + .05)
c3 <- cbind(c(1, 2, 3), c(1, 1.5, 1))
L1 <- Line(c1)
L2 <- Line(c2)
L3 <- Line(c3)
Ls1 <- Lines(list(L1), ID = "a")
Ls2 <- Lines(list(L2, L3), ID = "b")
sl1 <- SpatialLines(list(Ls1))
sl12 <- SpatialLines(list(Ls1, Ls2))
topojson_json(sl1)
topojson_json(sl12)
## From SpatialLinesDataFrame class
dat <- data.frame(
X = c("Blue", "Green"),
Y = c("Train", "Plane"),
Z = c("Road", "River"), row.names = c("a", "b")
)
sldf <- SpatialLinesDataFrame(sl12, dat)
topojson_json(sldf)
topojson_json(sldf, pretty = TRUE)
## From SpatialGrid
x <- GridTopology(c(0, 0), c(1, 1), c(5, 5))
y <- SpatialGrid(x)
topojson_json(y)
## From SpatialGridDataFrame
sgdim <- c(3, 4)
sg <- SpatialGrid(GridTopology(rep(0, 2), rep(10, 2), sgdim))
sgdf <- SpatialGridDataFrame(sg, data.frame(val = 1:12))
topojson_json(sgdf)
# From SpatialPixels
library("sp")
pixels <- suppressWarnings(SpatialPixels(SpatialPoints(us_cities[c("long", "lat")])))
summary(pixels)
topojson_json(pixels)
# From SpatialPixelsDataFrame
library("sp")
pixelsdf <- suppressWarnings(
SpatialPixelsDataFrame(points = canada_cities[c("long", "lat")], data = canada_cities)
)
topojson_json(pixelsdf)
# From sf classes:
if (require(sf)) {
## sfg (a single simple features geometry)
p1 <- rbind(c(0, 0), c(1, 0), c(3, 2), c(2, 4), c(1, 4), c(0, 0))
poly <- rbind(c(1, 1), c(1, 2), c(2, 2), c(1, 1))
poly_sfg <- st_polygon(list(p1))
topojson_json(poly_sfg)
## sfc (a collection of geometries)
p1 <- rbind(c(0, 0), c(1, 0), c(3, 2), c(2, 4), c(1, 4), c(0, 0))
p2 <- rbind(c(5, 5), c(5, 6), c(4, 5), c(5, 5))
poly_sfc <- st_sfc(st_polygon(list(p1)), st_polygon(list(p2)))
topojson_json(poly_sfc)
## sf (collection of geometries with attributes)
p1 <- rbind(c(0, 0), c(1, 0), c(3, 2), c(2, 4), c(1, 4), c(0, 0))
p2 <- rbind(c(5, 5), c(5, 6), c(4, 5), c(5, 5))
poly_sfc <- st_sfc(st_polygon(list(p1)), st_polygon(list(p2)))
poly_sf <- st_sf(foo = c("a", "b"), bar = 1:2, poly_sfc)
topojson_json(poly_sf)
}
## Pretty print a json string
topojson_json(c(-99.74, 32.45))
topojson_json(c(-99.74, 32.45)) %>% pretty()
}
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