Embankment mapping (R error)

[aly-kounta]

Hello everyone. I try to use the Whitebox tools for R.
I need compute the Embankment mapping using a DEM (1m resolution) and a Roads vector.
But i face on this error, i don't now what's the real problem, the DEM and vector file have the same projection in Lambert 93 for France. Tahnks for help:
Error in system(exeargs, intern = TRUE, ignore.stderr = ignore.stderr, :
'CreateProcess' a échoué au lancement de 'C:\WHITEB1\WHITEB2\WHITEB1\WBT\WHITEB2.EXE --run=EmbankmentMapping --dem="D:\DATA_INPUT_PROJET_BR\MNT_1m.tif" --road_vec="c("MEROUNUM0000002328953099", "MEROUNUM0000002328953203", "MEROUNUM0000002328953204", "MEROUNUM0000002328953121", "MEROUNUM0000002328953124", "MEROUNUM0000002245514653", "MEROUNUM0000002328953196", "MEROUNUM0000002328953400", "MEROUNUM0000002328953401", "MEROUNUM0000002328953402", "MEROUNUM0000002245484377

[brownag]

Hi @aly-kounta

It is hard to say for sure what the problem is, but likely the 'CreateProcess' failure to launch is because your WhiteboxTools binary is located in a folder where you don't have permissions to execute. Try installing the binary with install_whitebox() which will try a standard user-level path, that should work as long as you don't have more restrictive IT policies. Alternately, install somewhere you know you have permissions, or have a administrator privileged user do so, such as in the "Program Files" folder, and then manually set the exe_path argument to wbt_init() before running any tools.

[aly-kounta]

Hello sir!
Thanks for the feedback, I'll give it a try and see.

[brownag]

@aly-kounta

Looking closer at the error message abote, it may be that you have misspecified the road_vec argument. Can you please show the code you are trying to use?

[aly-kounta]

Hello Sir! @brownag. the error is noy yet solve. here the code:

Embankment mapping

Installer les packages nécessaires

#install.packages("whitebox")#
#install.packages("raster")
#install.packages("sf")

#if (!require("remotes")) install.packages('remotes')
#remotes::install_github("opengeos/whiteboxR", build = FALSE)

#install.packages("whitebox")

Charger les bibliothèques

library(whitebox)
library(raster)
library(sf)
library(terra) # lien vers la librairie terra: analyses raster et vecteur
library(gridExtra)

Spécifiez le chemin vers whitebox_tools.exe

#wbt_init()
wbt_init(exe_path = 'C:/Users/p01077/WhiteboxTools_win_amd64/WhiteboxTools_win_amd64/WBT/whitebox_tools.exe') # Chemin correct vers l'exécutable
wbt_version()

DEM

dem=rast("D:/DATA_INPUT_PROJET_BR/MNT_1m.tif")
road_vec = read_sf("D:/DATA_INPUT_PROJET_BR/Routes_D22.shp")
output <- "C:/Users/p01077/WhiteboxTools_win_amd64/WhiteboxTools_win_amd64/WBT/talus.tif" # Fichier raster de sortie
#plot(dem)
#plot(road_vec)

Embankment function.

wbt_embankment_mapping(
dem = dem,
road_vec = road_vec,
output = "C:/Users/p01077/WhiteboxTools_win_amd64/WhiteboxTools_win_amd64/WBT/talus.tif",
search_dist = 10, # Distance augmentée
min_road_width = 6,
typical_width = 30,
max_height = 2,
max_width = 60,
max_increment = 0.05,
spillout_slope = 4,
remove_embankments = FALSE,
verbose_mode = TRUE
)

[brownag]

It seems that you figured this out, but road_vec should either be a path to the input shapefile, or a SpatVector object for which terra::sources() returns the correct path.

[aly-kounta]

It seems to me that the method of importing files is not correct in WhiteboxTools, which expects file paths, not sf and terra objects. I convert the DEM raster to a file path instead of the rast() object. the same goes for the shapefile, not with read_sf(). on the other hand, the output raster after execution of the function is incorrect, with erroneous min and max values.

[brownag]

If an object contains a reference to file path (i.e. terra::sources() returns a file path) then it can be used as input. So SpatRaster, SpatVector, SpatVectorProxy etc. work. But in your example read_sf() reads into memory, so it is not in the correct format. I can probably add an error message for this case.

Note that the wbt() function has some additional options to convert heterogeneous R spatial objects to a suitable format to input in command line. In the case of an sf object in memory, that object needs to be first written to a temporary shapefile and the path to that temp file passed. See https://whiteboxr.gishub.org/articles/wbt-method.html for more details

[brownag]

on the other hand, the output raster after execution of the function is incorrect, with erroneous min and max values.

It is hard to say what the issue with output values is without having a copy of the sample data. If you can demonstrate that a valid command is generated (see command_only=TRUE argument to wbt_embankment_mapping()) which gives unexpected output, you can report the issue with the tool itself on the main whitebox-tools repository: https://github.com/jblindsay/whitebox-tools/issues

[aly-kounta]

Thank you very much @brownag , problem solved. The output was related to the projection between the raster and the vector. Both cocuhes are in lambert 93 but the vector was specified to zone CC48 of france.