eechidna (version 0.1)

aec_carto_f: aec_carto_f - run dorling ondata centers

Description

The dorling algorithm creates a non-contiguous cartogram by shifting circles to alleviate overlap, while roughly maintaining geographic proximity.

Usage

aec_carto_f(aec_data_sub, polygon.vertex = 6, name.text = TRUE,
  dist.ratio = dist.ratio, iteration = 100, xlab = "", ylab = "", ...)

Arguments

aec_data_sub

subset of data with centroids of electoral divisions

polygon.vertex

The number of vertice of the circle. Default to be 100. If polygon.vertex=4 then diamonds applies. If polygon.vertex=6, then hexagon applies.

name.text

whether to print the region names on the circles or polygons.

dist.ratio

The threshold to determine whether an attract force is added. It is applied to the ratio of the distance between two centroids and the sum of the two radii.

iteration

The limit of the number of iterations. Default to be 9999.

xlab

Label for dorling x axis, intermediate drawing

ylab

Label for dorling y axis, intermediate drawing

...

arguments to dorling function

Examples

library(dplyr)
library(ggplot2)
data(nat_map)
data(nat_data)
adelaide <- aec_extract_f(nat_data, ctr=c(138.6, -34.9), expand=c(2,3))
adelaide_carto <- aec_carto_f(adelaide) %>% rename(id=region)
ggplot(data=nat_map) + 
  geom_path(aes(x=long, y=lat, group=group, order=order),
                 colour="grey50") +
  geom_point(data=adelaide_carto, aes(x=x, y=y), size=4, alpha=0.4,
        colour="#f0027f") + 
        xlim(c(136, 140)) + ylim(-36, -33) +
        coord_equal()
adelaide_all <- merge(adelaide, adelaide_carto, by="id")
ggplot(data=nat_map) + 
  geom_path(aes(x=long, y=lat, group=group, order=order),
                 colour="grey50") +
  geom_point(data=adelaide_all, aes(x=long_c, y=lat_c), size=2, alpha=0.4,
              colour="#f0027f") + 
  geom_point(data=adelaide_all, aes(x=x, y=y), size=2, alpha=0.4,
                             colour="#f0027f") + 
  geom_segment(data=adelaide_all,
       aes(x=long_c, xend=x, y=lat_c, yend=y), colour="#f0027f") +
  xlim(c(136, 140)) + ylim(-37, -33) +
  coord_equal()