Cartograms are maps in which the areas of enumeration units $\text{(}$e.g. administrative divisions$\text{)}$ are proportional to quantitative data $\text{(}$e.g. population$\text{)}$. Generating cartograms with density-equalising map projections guarantees that geographic neighbours remain neighbours in the cartograms if all boundaries are infinitely dense sequences of points. However, computers represent boundaries with only finitely many points, often causing invalid topologies in the cartogram. This talk shows how line densification and topology-aware simplification solve this problem.
Funding
MOE-T2EP20221-0007
History
Journal/Conference/Book title
10th International Congress on Industrial and Applied Mathematics, Tokyo, Japan
Publication date
2023-08-22
Version
Published
Rights statement
Michael T Gastner, Nguyen Phong Le, Nihal Z Miaji and Adi Singhania (2023). Topology-aware algorithm for constructing cartograms from density-equalising map projections. Presented at the 10th International Congress on Industrial and Applied Mathematics, Tokyo, Japan.
Corresponding author
Michael T Gastner
Project ID
14612 (R-R22-A405-0003) Designing mobile-friendly cartograms for visualising geospatial data