In tributetotobler/ttt: Tribute to Tobler

knitr::opts_chunk$set(collapse = TRUE, 
                      fig.width = 7.2, 
                      fig.height = 4, 
                      margin = TRUE)
knitr::knit_hooks$set(margin = function(before, options, envir){
  if (before){
    par(mar=c(0,0,0,0))
  } 
})

Install

# remotes::install_git(url = "https://gitlab.huma-num.fr/ttt/ttt")

Load

library(ttt)

Data Import & Handling

library(sf)

# Import
crs <- "+proj=robin +lon_0=0 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84 +units=m +no_defs"

subregions <- st_read(system.file("subregions.gpkg", package="flowmapper")) %>% st_transform(crs)
migr <- read.csv(system.file("migrantstocks2019.csv", package="flowmapper"))

#  Selection, filtrage, traitement en amont

threshold <- 1500
migr <- migr[migr$fij >= threshold,]

Example 1

c <- ttt_flowmapper(
 x = subregions,
 xid = "id",
 df = migr,
 dfid = c("i","j"),
 dfvar = "fij"
)

Example 2

intra <- migr[migr$i == migr$j,c("i","fij")]
colnames(intra) <- c("id","nb")

plot(st_geometry(subregions), col = "#CCCCCC", border = "white", lwd = 0.5)
c <- ttt_flowmapper(
 x = subregions,
 xid = "id",
 df = migr,
 dfid = c("i","j"),
 dfvar = "fij",
 size = "thickness",
 type = "rect",
 decreasing = FALSE,
 add = TRUE,
 lwd = 1,
 col = "#00FF0090",
 border = "#4a0c25",
 k = NULL,
 df2 = intra,
 df2id = "id",
 df2var = "nb"
)

Example 3

crs <- "+proj=aeqd +lat_0=90 +lon_0=50 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs "
subregions2 <- st_transform(subregions, crs)

plot(st_geometry(subregions2), col = "#CCCCCC", border = "white", lwd = 0.5)
c <- ttt_flowmapper(
 x = subregions2,
 xid = "id",
 df = migr,
 dfid = c("i","j"),
 dfvar = "fij",
 add = TRUE
)

Example 4

crs <- "+proj=ortho +lat_0=42.5333333333 +lon_0=-72.53333333339999 +x_0=0 +y_0=0 +a=6370997 +b=6370997 +units=m +no_defs"
flows <- smoothr::densify(c[[3]], n = 30) %>% st_transform(crs)
plot(st_geometry(subregions) %>% st_transform(crs), col ="#CCCCCC", border = "white")
plot(st_geometry(flows), col ="#FF000099", add = TRUE)
plot(st_centroid(st_geometry(c[[2]])) %>% st_transform(crs), add = TRUE, pch = 20, cex = 1.3, col ="black")