Q. I’m trying to use diff command, but it is not working. I’d like to display those lines that are common to file1 and file2? How do I do it?
A. Use comm command; it compare two sorted files line by line. With no options, produce three column output. Column one contains lines unique to FILE1, column two contains lines unique to FILE2, and column three contains lines common to both files.
To Display Those Lines That Are Common to File1 and File2
Type the command as follows:
$ comm /path/to/file1/ /path/to/file2
$ comm -1 /path/to/file1/ /path/to/file2
$ comm -2 /path/to/file1/ /path/to/file2
$ comm -3 /path/to/file1/ /path/to/file2
Where,
- -1 : suppress lines unique to FILE1
- -2 : suppress lines unique to FILE2
- -3 : suppress lines that appear in both files
You can also try out perl code (it was posted by someone at comp.unix.shell news group):
$ perl -ne 'print if ($seen{$_} .= @ARGV) =~ /10$/' file1 file2
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And if you want to find the lines NOT common in 2 files, use diff
I used the line of perl to find the common lines between two files, but I needed it to ignore case. The solution, provided by mu was:
perl -ne ‘print if ($seen{lc $_} .= @ARGV) =~ /10$/’ file1 file2
Thanks mu!
Aengus
it does not work
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
I don’t see where you specify file2 in either option. I’m interested in the second option.
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)
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
Ah, yes, good point. I was coming at it from two files of stats for which I had removed duplicate lines and sorted.
Thanks for the Perl code. :-)
It works.
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.)
i tried it but it is not working
===============================
while read line
do
echo “Searching for : ”
echo $line
while read lines
do
if [ “$lines” = “$line” ]
then
echo $line
fi
done < $2
done < $1
=============================================
It works.
anyname.sh — contains the above written script
u have to change the privlges of the file to 777 :
chmod 777 anyname.sh
then run it :
./anyname.sh
file1 and file2 can be any text files.
U must run d script like dis only :
wid arguments .
————————————-
./anyname.sh
————————————-
U must run d script like dis only :
wid arguments .
————————————-
./anyname.sh (file1) (file2)
————————————-
In Unix lets assume, I have 2 files .. file1 and file2
In file1
13
14
15
16
17
20
21
23
24
27
and in file2
16
17
18
24
25
30
32
Question : I would like to print the common strings(words) listed in file1 and file2 in the column wise only. i.e,
16
17
24
grep -f file1 file2
will give the result as u expect
paste the code below into a file called intersect.sh
while read line
do
grep -n “^${line}$” $2;
done < $1
then make sure you have execute permissions on the file
chmod 777 intersect.sh
then run this command, substituting the names of your two files
./intersect.sh nameOfLongerFile nameOfShorterFile
Is there a quick way to get the matching lines plus (in one file) adjacent lines? The following works, but hits near the end of the files are incredibly inefficent:
while read p; do grep -A1 “$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.
The perl one-liner worked very well for me. Thanks for providing that. Much appreciated.
In python :
python nameofthescript.py file1 file2
You can comment prints of course
1) for i in `cat file1`; do grep –color $i file2; done
2) grep -f file1 file2
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.
i want to do this but with two strings saved in two bash variables… is this possible with comm?