23 comment

1. And if you want to find the lines NOT common in 2 files, use diff

2. I used the line of perl to find the common lines between two files, but I needed it to ignore case. The solution, provided by mu was:

   perl -ne ‘print if ($seen{lc $_} .= @ARGV) =~ /10$/’ file1 file2

   Thanks mu!

   Aengus

   1. it does not work

3. I am not able to find common lines between 2 files with comm -3.. I use diff instead:
   Use regex of contents of the file instead of \d+

   diff -y <(sort file1) out

   And for finding lines that are present in file1 but not in file2:
   diff –suppress-common-lines <(sort file1) ” > output

   1. I don’t see where you specify file2 in either option. I’m interested in the second option.

4. Why not:

   comm -1 -2 /path/to/file1/ /path/to/file2

   This works in the command line on OSX for showing on the common lines to the 2 files. (though perhaps it is limited to OSX’s flavor of BSD — haven’t tested elsewhere)

   1. It works only for sorted files, so you need:
      /path/to/file1 | sort > /path/to/file1_sorted
      /path/to/file2 | sort > /path/to/file2_sorted
      comm -1 -2 /path/to/file1_sorted/ /path/to/file2_sorted

      1. Ah, yes, good point. I was coming at it from two files of stats for which I had removed duplicate lines and sorted.

5. Thanks for the Perl code. :-)
   It works.

6. This script takes two files as arguments $1 and $2 and prints common lines in the
   two files.
   ===============================
   while read line
   do
   echo “Searching for : ”
   echo $line
   while read lines
   do
   if [ “$lines” = “$line” ]
   then
   echo $line
   fi
   done < $2

   done < $1
   ======================================
   save this into a file then run it ./anyname file1 file2
   NOTE : The input files must be intended i.e. no extra space in lines (i.e before or after lines.)

   1. i tried it but it is not working

      1. ===============================
         while read line
         do
         echo “Searching for : ”
         echo $line
         while read lines
         do
         if [ “$lines” = “$line” ]
         then
         echo $line
         fi
         done < $2

         done < $1
         =============================================
         It works.
         anyname.sh — contains the above written script
         u have to change the privlges of the file to 777 :
         chmod 777 anyname.sh
         then run it :
         ./anyname.sh

         file1 and file2 can be any text files.

         1. U must run d script like dis only :
            wid arguments .
            ————————————-
            ./anyname.sh
            ————————————-

            1. U must run d script like dis only :
               wid arguments .
               ————————————-
               ./anyname.sh (file1) (file2)
               ————————————-

7. In Unix lets assume, I have 2 files .. file1 and file2
   In file1
   13
   14
   15
   16
   17
   20
   21
   23
   24
   27
   and in file2
   16
   17
   18
   24
   25
   30
   32

   Question : I would like to print the common strings(words) listed in file1 and file2 in the column wise only. i.e,
   16
   17
   24

   1. grep -f file1 file2
      will give the result as u expect

8. paste the code below into a file called intersect.sh

   while read line
   do
   grep -n “^${line}$” $2;
   done < $1
   then make sure you have execute permissions on the file

   chmod 777 intersect.sh

   then run this command, substituting the names of your two files

   ./intersect.sh nameOfLongerFile nameOfShorterFile

9. Is there a quick way to get the matching lines plus (in one file) adjacent lines? The following works, but hits near the end of the files are incredibly inefficent:

   while read p; do grep -A1 “$p” file2 ; done <file1

   this'll match all lines from file1 in file2 (or at least the first match?) and provide the next line from file2 as well.

10. The perl one-liner worked very well for me. Thanks for providing that. Much appreciated.

11. In python :

    import sys,os
    file1 = open(sys.argv[1],"r")
    file2 = open(sys.argv[2],"r")
    
    lines1 = file1.readlines()
    lines2 = file2.readlines()
    print "File %s has %s lines" % (sys.argv[1],len(lines1))
    print "File %s has %s lines" % (sys.argv[2],len(lines2))
    
    found = []
    notfound = []
    for idx,l in enumerate(lines1) :
    	print "Doing line %s in file %s : %s" % (idx,sys.argv[1],l)
    	for idx2,l2 in enumerate(lines2) :
    		if l == l2 :
    			print "Found %s ( ==  %s ) in file %s at index %s" % (l,l2, sys.argv[2],idx2)
    			found.append(l)
    			continue
    			print "Found : %s , Not Found : %s" % (len(found),len(notfound))
    	notfound.append(l)
    	print "Found : %s , Not Found : %s" % (len(found),len(notfound)) 
    

    python nameofthescript.py file1 file2

    You can comment prints of course

12. 1) for i in `cat file1`; do grep –color $i file2; done
    2) grep -f file1 file2

13. In a file having following data

    adsdfsf 10 sdfd 10
    sdsgfjf 5 hdvfd 10
    gdyfdfd 20 jdfhd 564

    I want to compare column one with column two. Please any body knows reply to my mail id.

14. i want to do this but with two strings saved in two bash variables… is this possible with comm?

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