How to get consolidated count of delimiter occurrence

Question

I have a requirement to fetch the count the occurrence of '|' in each line of a file then match the count with given inputcount, needs to throw exception when the count is wrong.

Say if the inputcount=3 and the file has following content

s01|test|aaa|hh
S02|test|bbb
so3|test|ccc|oo

then exception should get thrown on executing the line 2 and it should exit the file.

Tried below Awk command to fetch the count for each lines, but I was not sure how to compare and throw the exception, when it not matches

awk ' {print (split($0,a,"\|")-1) }' test.dat

Can anyone please help me with it?

anubhava · Accepted Answer · 2021-05-03T11:10:44.617

2

You may use this awk:

awk -v inputcount=3 -F '\\|' 'NF && NF != inputcount+1 {exit 1}' file &&
 echo "good" || echo "bad"

Details:

-F '\\|' sets | as input field separator
NF != inputcount+1 will return true if any line doesn't have inputcount pipe delimiters.

edited May 03 '21 at 11:10

answered May 03 '21 at 11:00

anubhava

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Thanks for your reply. Since my file contains some of the line are empty, it always return bad. Can you please help me here – kaviya .P May 03 '21 at 11:10
ok check updated answer. It will ignore empty lines now – anubhava May 03 '21 at 11:11

score 2 · Answer 2 · answered May 03 '21 at 12:15

2

$ inputcount=3
$ awk -v c="$inputcount" 'gsub(/\|/,"&")  !=  c{exit 1}' file
$ echo $?
1

answered May 03 '21 at 12:15

Ed Morton

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tripleee · Answer 3 · 2021-05-03T12:31:53.850

0

Maybe try

awk -F '[|]' -v cols="$inputcount" 'NF != cols+1 {
    print FILENAME ":" FNR ":" $0 >"/dev/stderr"; exit 1 }' test.dat

The -F argument says to split on this delimiter; the number of resulting fields NF will be one more than there are delimiters, so we scream and die when that number is wrong.

edited May 03 '21 at 12:31

answered May 03 '21 at 11:00

tripleee

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score 0 · Answer 4 · answered May 03 '21 at 11:07

As you also tagged the post with python I will write a python answer that could be a simple script.

The core is:

with open(filename) as f:
    for n, line in enumerate(f):
        if line.count("|") != 3:
            print(f"Not valid file at line {n + 1}")

Than you can add some boilerplate:

import fileinput
import sys

with fileinput.input() as f:
    for n, line in enumerate(f):
        if line.count("|") != 3:
            print(f"Not valid file at line {n + 1}")
            sys.exit(1)

And with fileinput you can accept almost any sort of input: see Piping to a python script from cmd shell

How to get consolidated count of delimiter occurrence

4 Answers4