How to count number of occurances of string in a file?

Shell Programming and Scripting
1

Gurus,

Need little guidance.
I have A.txt and B.txt file. B.txt file contains Unique strings.
Sample content of B.txt file for which i cut the fourth column uniquely and output directed to B.txt file

And A.txt file contains the above string as a fourth column which is last column.
So A.txt file fourth column content is

while read line
    do
    COUNT=`grep "$line" A.txt | wc -l`
    echo $line "," $COUNT >> output.txt
    done < B.txt

Output.txt file displays output

Here ghjjj should display 1 instead 2...
Can anybody guide me the better way to get this.

Thanks in advance!!!

2

Take a look at the man pages of command "uniq" and "comm"

uniq -c A.txt

Note that this assume A.txt has previously been sorted.

sort A.txt | uniq -c
3

Hi,

I would change a little bit your script, test this:

#!/bin/sh

while read line; do
    count=$(grep "^${line}$" a.txt | wc -l)
    echo "$line $count"
done < b.txt

Regards,

4

That's because in A.txt, the fourth line also contains "ghjjj", so it greps 2
So with awk...

awk 'NR==FNR{arr[$0]++;next}arr[$0]{print $0,arr[$0]}' A.txt B.txt
5

You can modify your script like this:

while read -r line
do     
  COUNT=$(grep -Fcx "$line" A.txt)
  echo "$line , $COUNT"
done < B.txt > output.txt

It is similar to birei's suggestion

6

yeah its correct but the above solution is not working...

---------- Post updated at 05:11 AM ---------- Previous update was at 04:59 AM ----------

hi..
I am getting 0 for every line....i thing that grep wc -l is not working...
i tried giving in ` ` but giving error that command not found

7

What error do you get when you run it?

Use nawk if you are on Solaris...

8

nope..i am on linux..it doesnot show any output...tried to redirecting to other file as well..