# nc_cartogram: Calculate Non-Contiguous Cartogram Boundaries In cartogram: Create Cartograms with R

## Description

Construct a non-contiguous area cartogram (Olson 1976).

## Usage

 ```1 2 3 4 5 6 7 8``` ```nc_cartogram(shp, weight, k = 1, inplace = T) ## S3 method for class 'SpatialPolygonsDataFrame' nc_cartogram(shp, weight, k = 1, inplace = T) ## S3 method for class 'sf' nc_cartogram(shp, weight, k = 1, inplace = T) ```

## Arguments

 `shp` SpatialPolygonDataFrame or an sf object `weight` Name of the weighting variable in shp `k` Factor expansion for the unit with the greater value `inplace` If TRUE, each polygon is modified in its original place, if FALSE multi-polygons are centered on their initial centroid

## Value

An object of the same class as shp with resized polygon boundaries

## References

Olson, J. M. (1976), Noncontiguous Area Cartograms. The Professional Geographer, 28: 371–380. doi:10.1111/j.0033-0124.1976.00371.x

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25``` ```library(maptools) library(cartogram) library(rgdal) data(wrld_simpl) # Remove uninhabited regions afr <- spTransform(wrld_simpl[wrld_simpl\$REGION==2 & wrld_simpl\$POP2005 > 0,], CRS("+init=epsg:3395")) # Create cartogram afr_nc <- nc_cartogram(afr, "POP2005") # Plot plot(afr) plot(afr_nc, add = TRUE, col = 'red') # Same with sf objects library(sf) afr_sf = st_as_sf(afr) afr_sf_nc <- nc_cartogram(afr_sf, "POP2005") plot(st_geometry(afr_sf)) plot(st_geometry(afr_sf_nc), add = TRUE, col = 'red') ```

cartogram documentation built on May 22, 2018, 5:04 p.m.