tobler_1979.R

library(sf)

## Linking to GEOS 3.6.2, GDAL 2.2.4, proj.4 4.9.3

library(spData)

## To access larger datasets in this package, install the spDataLarge
## package with: `install.packages('spDataLarge',
## repos='https://nowosad.github.io/drat/', type='source'))`

library(dplyr)

## 
## Attaching package: 'dplyr'

## The following objects are masked from 'package:stats':
## 
##     filter, lag

## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union

library(tidyr)
statepop = historydata::us_state_populations %>% select(-GISJOIN) %>% rename(NAME = state)

statepop_wide = spread(statepop, year, population, sep = "_")
statepop_sf = left_join(spData::us_states, statepop_wide)

## Joining, by = "NAME"

library(anglr)
library(silicate)
## we only need cheap triangles, DEL is unnecessary
x <- TRI(statepop_sf)
xz <- copy_down(x, x$object$year_1900)

## Joining, by = "triangle_"

## [1] "TRI"

plot3d(xz)
rgl::aspect3d(1, 1, 0.1)
rgl::rglwidget()