extract number from file name

[liondari]

Hello,

I would like to extract an int number from a file name. I have
hundreds of files with the following names:
Qhull_1000_001.xyz ... Qhull_15000_150.xyz.
Now, I need the first number to be extracted and saved into a file. The second number I use for steering a for loop.
Thanks in advance

 

[p5wizard]

does this help?

ls | cut -d_ -f2 > /path/to/numbersfile


HTH,

p5wizard

 

[bigoldbulldog]

Here are some more thoughts...
Also, be more specific.

for fn in Qhull_*_*.xyz
do
  CT=$(expr "$fn" : ".*_0*\([0-9]*\)\..*")
  echo $fn $(expr "$fn" : ".*_\(.*\)_.*") $CT >> /path/to/numberedfile
  # additional for loop here, if desired
done

Cheers,
ND

[small]bigoldbulldog AT hotmail[/small]

 

[SamBones]

A Korn shell variable editing solution...

#!/bin/ksh

for FILE in Qhull_*_*.xyz
do
    NUM1=${FILE#Qhull_}   # Remove the front 'Qhull_'
    NUM1=${NUM1%%_*}      # Remove the back '_*'

    NUM2=${FILE##*_}      # Remove the front '*_'
    NUM2=${NUM2%.*}       # Remove the back '.*'

    print "1st number: ${NUM1}"
    print "2nd number: ${NUM2}"

    print ${NUM1} >> /path-to/numbers.file
done