dynamically pass string to Rscript argument with sed - r

Question

I wrote a script in R that has several arguments. I want to iterate over 20 directories and execute my script on each while passing in a substring from the file path as my -n argument using sed. I ran the following:
find . -name 'xray_data' -exec sh -c 'Rscript /Users/Caitlin/Desktop/DeMMO_Pubs/DeMMO_NativeRock/DeMMO_NativeRock/R/scipts/dataStitchR.R -f {} -b "{}/SEM_images" -c "{}/../coordinates.txt" -z ".tif" -m ".tif" -a "Unknown|SEM|Os" -d "overview" -y "overview" --overview "overview.*tif" -p FALSE -n "`sed -e 's/.*DeMMO.*[/]\(.*\)_.*[/]xray_data/\1/' "{}"`"' sh {} \;
which results in this error:
ubs/DeMMO_NativeRock/DeMMO_NativeRock/R/scipts/dataStitchR.R -f {} -b "{}/SEM_images" -c "{}/../coordinates.txt" -z ".tif" -m ".tif" -a "Unknown|SEM|Os" -d "overview" -y "overview" --overview "overview.*tif" -p FALSE -n "`sed -e 's/.*DeMMO.*[/]\(.*\)_.*[/]xray_data/\1/' "{}"`"' sh {} \;
sh: command substitution: line 0: syntax error near unexpected token `('
sh: command substitution: line 0: `sed -e s/.*DeMMO.*[/](.*)_.*[/]xray_data/1/ "./DeMMO1/D1T3rep_Dec2019_Ellison/xray_data"'
When I try to use sed with my pattern on an example file path, it works:
echo "./DeMMO1/D1T1exp_Dec2019_Poorman/xray_data" | sed -e 's/.*DeMMO.*[/]\(.*\)_.*[/]xray_data/\1/'
which produces the correct substring:
D1T1exp_Dec2019
I think there's an issue with trying to use single quotes inside the interpreted string but I don't know how to deal with this. I have tried replacing the single quotes around the sed pattern with double quotes as well as removing the single quotes, both result in this error:
sed: RE error: illegal byte sequence
How should I extract the substring from the file path dynamically in this case?

Answer 1

To loop through the output of find.
while IFS= read -ru "$fd" -d '' files; do
echo "$files" ##: do whatever you want to do with the files here.
done {fd}< <(find . -type f -name 'xray_data' -print0)
No embedded commands in quotes.
It uses a random fd just in case something inside the loop is eating/slurping stdin
Also -print0 delimits the files with null bytes, so it should be safe enough to handle spaces tabs and newlines on the path and file names.
A good start is always put an echo in front of every commands you want to do with the files, so you have an idea what's going to be executed/happen just in case...

Answer 2

This is the solution that ultimately worked for me due to issues with quotes in sed:
for dir in `find . -name 'xray_data'`;
do sampleID="`basename $(dirname $dir) | cut -f1 -d'_'`";
Rscript /Users/Caitlin/Desktop/DeMMO_Pubs/DeMMO_NativeRock/DeMMO_NativeRock/R/scipts/dataStitchR.R -f "$dir" -b "$dir/SEM_images" -c "$dir/../coordinates.txt" -z ".tif" -m ".tif" -a "Unknown|SEM|Os" -d "overview" -y "overview" --overview "overview.*tif" -p FALSE -n "$sampleID";
done