dev/tests/test_chi.R

In VincentGodard/gtbox: A Geomorphology Toolbox With Various Functions For The Analysis of Topography and Surface Processes

library("gtbox")
library("terra")
library("tictoc")
gisbase = "/usr/lib/grass78/"

# get DEM
data("dem_cevennes",package = "gtbox")
dem = rast(dem_cevennes)
rm(dem_cevennes)

st = process_dem(dem,th_px=2000,gisbase=gisbase)
net = get_network(st,gisbase)
out = get_outlets(st,large = 10e4)
bas = get_basins(st,out,gisbase)


# compute chi
tic()
chi = compute_chi(st,starting_points=out,a0=1000,mn=0.5,gisbase)
toc()


chi_map = streams2basins(st,chi,FUN="median")



# # network topology
# nxt_id = get_next(st$st_id,st$dir)
# seg = as.data.frame(c(st$st_id,nxt_id,st$acc))
# colnames(seg)<-c("id","down","acc")
# seg = seg[seg$id!=seg$down,]
# # those that drain outside
# ids = unlist(unique(st$st_id))
# tmp = data.frame(id=ids[!ids%in%seg$id],down=-1,acc=NA)
# seg = rbind(seg,tmp)
#
# seg$up1 = NA
# seg$up2 = NA
# seg$up3 = NA
# for(i in 1:nrow(seg)){
#   up = seg[seg$down==seg$id[i],]$id
#   acc = seg[seg$down==seg$id[i],]$acc
#   up= up[order(acc)]
#   if(length(up)==1){
#     seg$up1[i]=up[1]
#     }
#   if(length(up)==2){
#     seg$up1[i]=up[1]
#     seg$up2[i]=up[2]
#   }
#     if(length(up)==3){
#       seg$up1[i]=up[1]
#       seg$up2[i]=up[2]
#       seg$up3[i]=up[3]
#
#   }
#   }