Convert map projection of a object of class prevR.

Source: R/changeproj.prevR.r

This function converts map projection (and/or datum) used by an object of class prevR into another one.

# S4 method for prevR
changeproj(object, proj)

Arguments

object

object of class prevR.

proj

new map projection. One of (i) character: a string accepted by GDAL, (ii) integer, a valid EPSG value (numeric), or (iii) an object of class crs, see sf::st_crs().

Value

Return object expressed in the projection proj.

Details

changeproj() transform the columns "x" and "y" of the slot clusters of object and convert boundary using the new map projection defined by proj.

If applicable, the slot rings will be recalculated.

Examples

print(fdhs)
#> Object of class 'prevR'
#> Number of clusters: 401
#> Number of observations: 8000
#> Number of positive cases: 810
#> The dataset is weighted.
#> 
#> National prevalence: 10.12%
#> National weighted prevalence: 10.16%
#> 
#> Projection used: +proj=longlat +datum=WGS84
#> 
#> Coordinate range
#>        min     max
#> x -5.37750  3.6850
#> y  4.80326 14.1225
#> 
#> Boundary coordinate range
#>      xmin      ymin      xmax      ymax 
#> -5.518916  4.736723  3.851701 15.082593 
plot(fdhs, axes = TRUE, main = "Projection: longitude/latitude")


fdhs2 <- changeproj(
  fdhs,
  "+proj=utm +zone=30 +ellps=WGS84 +datum=WGS84 +units=m +no_defs"
)
print(fdhs2)
#> Object of class 'prevR'
#> Number of clusters: 401
#> Number of observations: 8000
#> Number of positive cases: 810
#> The dataset is weighted.
#> 
#> National prevalence: 10.12%
#> National weighted prevalence: 10.16%
#> 
#> Projection used: +proj=utm +zone=30 +ellps=WGS84 +datum=WGS84 +units=m +no_defs
#> 
#> Coordinate range
#>        min     max
#> x 240094.2 1231995
#> y 531003.3 1562155
#> 
#> Boundary coordinate range
#>      xmin      ymin      xmax      ymax 
#>  224228.1  523628.1 1251165.0 1669034.2 
plot(fdhs2, axes = TRUE, main = "Projection: UTM Zone 30")