Forest Information from LiDAR data-your title

[utterances-bot]

Forest Information from LiDAR data-your title

https://gisma-courses.github.io/gi-modules/gi-modules/post/2021-11-20-forest-information-from-lidar-data/

[Muenchj4]

Trying to run "make_CHM_tiles.R" and reading the given las File the warning message came: "Invalid data: ScanAngleRank greater than 90 degrees".
Further trying lasnormalize the warning message came: "1: lidR::lasnormalize is deprecated. Use normalize_height instead.
2: There were 14 degenerated ground points. Some X Y Z coordinates were repeated. They were removed.
3: There were 180 degenerated ground points. Some X Y coordinates were repeated but with different Z coordinates. min Z were retained."
At the end when trying to visualize using mapview the error came: "Error in if (x == "" | x == ".") { : argument is of length zero".
How can I handle this problem?

[gisma]

everythng fine so far just dont use mapview. Try to plot the result

[Muenchj4]

Thank you. The picture is plotted. But why does mapview not work? Zitat von Chris Reudenbach ***@***.***>:

…

everythng fine so far just dont use mapview. Try to plot the result -- You are receiving this because you commented. Reply to this email directly or view it on GitHub: #4 (comment)

[Muenchj4]

Now, I am trying to run the Script using MOF_las file. But it does not know "espg_number". What should I input instead?

[gisma]

@Muenchj4 we discussed during the last course it is: https://epsg.io/25832

[Muenchj4]

thank you. Zitat von Chris Reudenbach ***@***.***>:

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@Muenchj4 we discussed during the last course it is: https://epsg.io/25832 -- You are receiving this because you were mentioned. Reply to this email directly or view it on GitHub: #4 (comment)

[Muenchj4]

Ok I have set epsg_number = 25832.
p2r and knnidw worked well. But trying to normalize height the error came: Processing [========>-------------------------------------------------------------------------------------------------------] 8% (1/12) eta: 9sError: Dataset copy failed
What could be the problem?

[Muenchj4]

sorry, normalize_height also worked well, but it was not able to grid canopy.

[Muenchj4]

I have found the problem myself. There was not setted a path normalized. I set it myself and rast was able to write the file "chm_distmin_1m", plotted it, but mapview did not work again, since it could not find the function "pal".

[gisma]

@Muenchj4 yup the col function pal is not defined. Just delete the row

[Muenchj4]

OK, the chm catalog is shown with mapview. Thank godness. Zitat von Chris Reudenbach ***@***.***>:

…

@Muenchj4 yup the col function `pal` is not defined. Just delete the row -- You are receiving this because you were mentioned. Reply to this email directly or view it on GitHub: #4 (comment)

[GeoKL]

Hello,
the script is running, but whenever I try to knit it (for putting it on the website) I get the error:

"C:/Program Files/RStudio/bin/pandoc/pandoc" +RTS -K512m -RTS agis_lidar_13-12.knit.md --to html4 --from markdown+autolink_bare_uris+tex_math_single_backslash --output agis_lidar_13-12.html --lua-filter "E:\edu\Packages\rmarkdown\rmarkdown\lua\pagebreak.lua" --lua-filter "E:\edu\Packages\rmarkdown\rmarkdown\lua\latex-div.lua" --self-contained --variable bs3=TRUE --standalone --section-divs --template "E:\edu\Packages\rmarkdown\rmd\h\default.html" --no-highlight --variable highlightjs=1 --variable theme=bootstrap --include-in-header "C:\Users\Kathi\AppData\Local\Temp\Rtmp4UVnEJ\rmarkdown-str23f05223275.html" --mathjax --variable "mathjax-url:https://mathjax.rstudio.com/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML"
pandoc.exe: Cannot decode byte '\xb2': Data.Text.Internal.Encoding.decodeUtf8: Invalid UTF-8 stream
Error: pandoc document conversion failed with error 1
Execution halted

What could this be about? Online I didn't find anything about this..

[gisma]

Please sent or upload the markdown file

[GeoKL]

@gisma took me a while, but now I did and sent you an invite.

[Muenchj4]

Er findet momentan bei mir die Funktion "get_vrt_img" nicht. Wie kann ich diese Funktion einbauen?

[Muenchj4]

Ich habe das "mof_chm_one_tile.tif" nochmals zu plotten versucht. Es ist prinzipiell auch immer noch im Ordner. Er gibt aber die Meldung aus: Error in h(simpleError(msg, call)) :
Fehler bei der Auswertung des Argumentes 'x' bei der Methodenauswahl für Funktion 'plot': object 'mof_chm_one_tile.tif' not found

[Muenchj4]

Ich habe den Fehler gefunden und den Katalog jetzt erstellt.

[gisma]

versuchen sie es mal mit raster::plot() zu plotten.

[gisma]

das ist eine Funktion die ich ihnen im Kurskontext zur Verfügung gestellt hatte.

get_vrt_img = function(name,path,tag,rasterStack = TRUE) {
  fList = list.files(path, 
                     pattern = glob2rx(paste0("*",tag,".tif")),
                     full.names = TRUE)
  
  res = invisible(gdalUtils::mosaic_rasters(gdalfile = fList,
                            output_Raster = TRUE,
                            dst_dataset = paste0(path,name,".tif"),verbose = FALSE))
  
  if (rasterStack) return(raster::stack(paste0(path,name,".tif")))
  
}