Help for package mapiso (original) (raw)
| Type: | Package |
|---|---|
| Title: | Create Contour Polygons from Regular Grids |
| Version: | 0.3.0 |
| Description: | Regularly spaced grids containing continuous data are transformed to contour polygons. A grid can be defined by a data.frame (x, y, value), an 'sf' object or a raster from 'terra'. |
| URL: | https://github.com/riatelab/mapiso |
| BugReports: | https://github.com/riatelab/mapiso/issues/ |
| Depends: | R (≥ 3.6.0) |
| Imports: | sf, isoband |
| Suggests: | covr, mapsf, terra, tinytest |
| License: | GPL (≥ 3) |
| Encoding: | UTF-8 |
| RoxygenNote: | 7.2.3 |
| NeedsCompilation: | no |
| Packaged: | 2023-05-12 11:52:16 UTC; tim |
| Author: | Timothée Giraud  [cre, aut] |
| Maintainer: | Timothée Giraud timothee.giraud@cnrs.fr |
| Repository: | CRAN |
| Date/Publication: | 2023-05-12 12:20:02 UTC |
Package description
Description
Regularly spaced grids containing continuous data are transformed into contour polygons. A grid can be defined by a data.frame (x, y, value), an sf object or a terra SpatRaster.
Create Contour Polygons from Regular Grids
Description
Regularly spaced grids containing continuous data are transformed into contour polygons. A grid can be defined by a data.frame (x, y, value), an sf object, a terra SpatRaster or SpatVector.
Usage
mapiso(x, var, breaks, nbreaks = 8, mask, coords, crs)
Arguments
| x | a data.frame, an sf object or a SpatRaster |
|---|---|
| var | name of the variable, for data.frames and sf objects only |
| breaks | list of break values (default to equal interval) |
| nbreaks | number of classes |
| mask | an sf object or SpatVector of polygons or multipolygons.mask is used to clip contour polygons |
| coords | names of the coordinates variables (e.g. c("lon", "lat")), for data.frames only |
| crs | CRS code (e.g. "epsg:2154"), for data.frames only. |
Value
The output is an sf object of polygons (or a SpatVector if xis a SpatVector). The data.frame contains three fields: id (id of each polygon), isomin and isomax (minimum and maximum breaks of the polygon).
Examples
# sf, using a mask
library(sf)
s <- st_read(system.file("gpkg/elevation.gpkg", package = "mapiso"),
layer = "elevation", quiet = TRUE
)
m <- st_read(system.file("gpkg/elevation.gpkg", package = "mapiso"),
layer = "com", quiet = TRUE
)
isos <- mapiso(
x = s, var = "elevation",
mask = m
)
plot(isos)
# data.frame, using user breaks values
d <- read.csv(system.file("csv/elevation.csv", package = "mapiso"))
bks <- c(98, 100, 150, 200, 250, 300, 350, 400, 412.6)
isod <- mapiso(
x = d, var = "elevation",
breaks = bks, coords = c("x", "y"), crs = "epsg:2154"
)
plot(isod)
if (require(mapsf, quietly = TRUE)) {
mf_map(isod, "isomin", "choro", breaks = bks, leg_title = "Elevation")
}
## Not run:
if (require(terra, quietly = TRUE)) {
# terra SpatRaster
r <- rast(system.file("tif/elevation.tif", package = "mapiso"))
isor <- mapiso(x = r)
plot(r)
plot(st_geometry(isor), add = TRUE, col = NA)
# terra SpatVector
s_terra <- vect(s)
m_terra <- vect(m)
isost <- mapiso(
x = s_terra, var = "elevation", mask = m_terra
)
plot(isost)
}
## End(Not run)