text-processing awk – How to Filter Based on Field Value in awk

awktext processing

I want to print the countries which which have to after ~:.

welcome~:to~:Germany
welcome~:no please~:Italy
welcome~:to~:Brazil
welcome~:not ok~:China

Note: I do not know what will be there other than "to". It can be anything and can be changed (like no please, not ok).

I am tried using cut, awk, sed. But I am unable to figure out.

awk -F "~:" '{print $2 $NF}'

But I get output like:

toGermany
no pleaseItaly
toBrazil
not okChina

How to filter countries other than to.

UPDATE:

Alternative solution:(Figured out with cut) 🙂

grep -v "to" |cut -d ':' -f3

Best Answer

As you are using ~: as field separator you can check if second field is equal to to and to print third field which is the country:

awk -F"~:" '$2 == "to" { print $3; }' file

Result:

Germany
Brazil

Related Solutions

Awk from different lines

awk solution:

awk 'v && NR==n{ print $6,v > "result.txt" }/^!/{ v=$5; n=NR+1 }' file

<condition1> { <statement> ... }<condition2>{ <statement> ... } - conditions with respective statements will be evaluated consecutively
/^!/{ v=$5; n=NR+1 } - on encountering line starting with ! - capture the 5th field value $5 and plan the next line number NR+1 (assigning to variable n)
v && NR==n - if we have the 1st crucial number v and the current record number NR is the needed "next line number" n - print the values into file result.txt

The result.txt file contents:

188 -9744.24963670
140 -9744.30001681
155 -9744.33953891
164 -9744.36584201
154 -9744.37925372
153 -9744.39185493
160 -9744.39836617

Does AWK have similar ability as SED to find line ranges based on text in line rather than line number

The OP's problem was caused by file file using CR (\r / ascii 13) instead of LF (\n / ascii 10) as line terminators as expected by sed. Using CR was the convention used in classic MacOS; as a non Mac user, the only use of it I've met with in the wild in the last two decades was in PDF files, where it greatly complicates any naive PDF parser written in perl (unlike RS in mawk and gawk, $/ in perl cannot be a regex).

As to the question from the title, yes, awk supports range patterns, and you can freely mix regexps and line number predicates (or any expression) in them. For example:

NR==1,/rex/   # all lines from the 1rst up to (and including)
          # the one matching /rex/

/rex/,0   # from the line matching /rex/ up to the end-of-file.

awk's ranges are different from sed's, because in awk the end predicate could also match the line which started the range. sed's behavior could be emulated with:

s=/start/, !s && /last/ { s = 0; print }

However, ranges in awk are still quite limited because they're not real expression (they cannot be negated, made part of other expressions, used in if(...), etc). Also, there is no magic: if you want to express something like a range with "context" (eg. /start/-4,/end/+4) you'll have to roll your own circular buffer and extra logic.

Best Answer

Related Solutions

Awk from different lines

Does AWK have similar ability as SED to find line ranges based on text in line rather than line number

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