how do i find the count of multiple words in a text file?

Question

I am able to find the number of times a word occurs in a text file, like in Linux we can use:

cat filename|grep -c tom

My question is, how do I find the count of multiple words like "tom" and "joe" in a text file.

Answer 1

Since you have a couple names, regular expressions is the way to go on this one. At first I thought it was as simple as just a grep count on the regular expression of joe or tom, but fount that this did not account for the scenario where tom and joe are on the same line (or tom and tom for that matter).

test.txt:

tom is really really cool!  joe for the win!
tom is actually lame.


$ grep -c '\<\(tom\|joe\)\>' test.txt
2

As you can see from the test.txt file, 2 is the wrong answer, so we needed to account for names being on the same line.

I then used grep -o to show only the part of a matching line that matches the pattern where it gave the correct pattern matches of tom or joe in the file. I then piped the results into number of lines into wc for the line count.

$ grep -o '\(joe\|tom\)' test.txt|wc -l
       3

3...the correct answer! Hope this helps