DHBins: hexmaps for NZ

The DHBins package lets you show statistics for New Zealand Regional Councils and District Health Boards on a hexagonal map, making comparisons easy by size or colour. For categorical data, you can split each hex into six triangles. This was my first ever set of ggplot geoms!

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1. DHBins: hexmaps for NZ Thomas Lumley University of Auckland 2020/2/22 1 / 18
2. Maps are hard (One Sheep, One Vote) 2 / 18
3. NZ District Health Boards 3 / 18
4. NZ Regional Council Areas 4 / 18
5. Statebins Originally from Washington Post graphics desk 5 / 18
6. District Health Boards 6 / 18
7. Regional Councils 7 / 18
8. library(DHBins) data(immune) immune$vax_pct<-cut(immune$Pcttotal,c(0,.80,.85,.90,.95,1)) ggplot(immune)+ geom_dhb(aes(fill=vax_pct,map_id=dhb_fixname(DHB)))+ scale_fill_viridis_d(drop=FALSE)+ geom_label_dhb(short=TRUE,colour="white") 8 / 18
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10. Regional councils (and triangles) data(region_ethnicity) tri_eth<-tri_alloc(as.matrix(region_ethnicity[,-1]), classes=c("Asian","Euro","Maori","MELAA","Pacific"), names=region_ethnicity$Area) tri_data<-data.frame(Region=rep(rownames(tri_eth),6), ethnicity=as.vector(tri_eth), tri_id=rep(1:6,each=nrow(tri_eth))) ggplot(tri_data)+ geom_regiontri(aes(map_id=Region,class_id=tri_id, fill=ethnicity))+ geom_label_region(colour="Black", short=TRUE,cex=4) 10 / 18
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12. No, it isn't a pie chart (what is wrong wrong with you people?) 12 / 18
13. Real ggplot geoms (they will layer and facet) ggplot(immune)+ geom_dhb(aes(map_id=dhb_fixname(DHB)),fill="white", colour="grey",coord=FALSE)+ geom_dhb(aes(fill=vax_pct,map_id=dhb_fixname(DHB), radius=sqrt(Ntotal)),alpha=0.5)+ scale_fill_viridis_d(drop=FALSE) data(immune_long) ggplot(immune_long) + geom_dhb(aes(map_id=dhb_fixname(DHB),fill=pct_vax), alpha=0.5,colour="lightgrey") + scale_fill_viridis_d(drop=FALSE)+ geom_label_dhb(short=TRUE,colour="black",cex=3)+ facet_wrap(~ethnicity) 13 / 18
14. Layer 14 / 18
15. Facet 15 / 18
16. How to write a geom geom_dhb, geom_region based on geom_map also needs coord_fixed, expand_limits, axis themes returns a list of ggplot objects needs new GeomDHBMap based on GeomMap so hex size can depend on data, can't just call geom_map geom_label_dhb, geom_label_region just calls geom_text 16 / 18
17. How to triangle Sainte-Laguë algorithm, as in MMP elections number of triangles is round(6*n/N) where n is count in that class and N is chosen to get exactly 6 hexes allocated 17 / 18
18. Where to get it github/tslumley/DHBins CRAN: DHBins arxiv.org: 1912.04435 https://notstatschat.rbind.io/2019/11/07/hexmaps-for-nz-district-health-boards/ (mostly about the base graphics functions) 18 / 18