SED command inside a loop - linux

Question

Hello: I have a lot of files called test-MR3000-1.txt to test-MR4000-1.nt, where the number in the name changes by 100 (i.e. I have 11 files),
$ ls test-MR*
test-MR3000-1.nt test-MR3300-1.nt test-MR3600-1.nt test-MR3900-1.nt
test-MR3100-1.nt test-MR3400-1.nt test-MR3700-1.nt test-MR4000-1.nt
test-MR3200-1.nt test-MR3500-1.nt test-MR3800-1.nt
and also a file called resonancia.kumac which in a couple on lines contains the string XXXX.
$ head resonancia.kumac
close 0
hist/delete 0
vect/delete *
h/file 1 test-MRXXXX-1.nt
sigma MR=XXXX
I want to execute a bash file which substitutes the strig XXXX in a file by a set of numbers obtained from the command ls *MR* | cut -b 8-11.
I found a post in which there are some suggestions. I try my own code
for i in `ls *MR* | cut -b 8-11`; do
sed -e "s/XXXX/$i/" resonancia.kumac >> proof.kumac
done
however, in the substitution the numbers are surrounded by sigle qoutes (e.g. '3000').
Q: What should I do to avoid the single quote in the set of numbers? Thank you.

Answer 1

This is a reproducer for the environment described:
for ((i=3000; i<=4000; i+=100)); do
touch test-MR${i}-1.nt
done
cat >resonancia.kumac <<'EOF'
close 0
hist/delete 0
vect/delete *
h/file 1 test-MRXXXX-1.nt
sigma MR=XXXX
EOF
This is a script which will run inside that environment:
content="$(<resonancia.kumac)"
for f in *MR*; do
substring=${f:7:3}
echo "${content//XXXX/$substring}"
done >proof.kumac
...and the output looks like so:
close 0
hist/delete 0
vect/delete *
h/file 1 test-MR300-1.nt
sigma MR=300
There are no quotes anywhere in this output; the problem described is not reproduced.

Answer 2

or if it could be perl:
#!/usr/bin/perl
#ls = glob('*MR*');
open (FILE, 'resonancia.kumac') || die("not good\n");
#cont = <FILE>;
$f = shift(#ls);
$f =~ /test-MR([0-9]*)-1\.nt/;
$nr = $1;
#out = ();
foreach $l (#cont){
if($l =~ s/XXXX/$nr/){
$f = shift(#ls);
$f =~ /test-MR([0-9]*)-1\.nt/;
$nr = $1;
}
push #out, $l;
}
close FILE;
open FILE, '>resonancia.kumac' || die("not good\n");
print FILE #out;
That would replace the first XXXX with the first filename, what seemed to be the question before change.