how to loop over pattern from a file with grep [duplicate]

Question

I am trying to grep a series of patterns that are, one per line, in a text file (list.txt), to find how many matches there are of each pattern in the target file (file1). The target file looks like this:

$ cat file1 2346 TGCA 2346 TGCA 7721 GTAC 7721 GTAC 7721 CTAC

And I need counts of each numerical pattern (2346 and 2271).

I have this script that works if you provide a list of the patterns in quotes:

 $ for p in '7721' '2346'; do printf '%s = ' "$p"; grep -c "$p" file1; done 7721 = 3 2346 = 2

What I would like to do is search for all patterns in list.txt:

$ cat list.txt 7721 2346 6555 25425 22 125 .... 19222

How can I convert my script above to look in the list.txt and search for each pattern, and return the same output as above (pattern = count) e.g.:

2346 = 2 7721 = 3 .... 19222 = 6

Does it matter that one of those 7721 lines is different then the other two? — Etan Reisner
– Etan Reisner, Commented Apr 7, 2015 at 14:46
I don't see how this is a duplicate of that question? There are plenty of questions of this same form that it could reasonably be a duplicate of but not that one. — Etan Reisner
– Etan Reisner, Commented Apr 7, 2015 at 14:50
it doesn't matter. Infact, the string after the ID may vary across many matches. — LP_640
– LP_640, Commented Apr 7, 2015 at 14:58

Kent · Accepted Answer · 2015-04-07 14:46:10Z

2

try this awk oneliner:

 awk 'NR==FNR{p[$0];next}$1 in p{p[$1]++}END{for(x in p)print x, p[x]}' list.txt file

answered Apr 7, 2015 at 14:46

Kent

197k36 gold badges248 silver badges317 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

how to loop over pattern from a file with grep [duplicate]

1 Answer 1

Comments

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Linked

Related