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Replace substrings in awk

 
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# 1  
Old 01-18-2013
Replace substrings in awk
Hi !

my input looks like that:
Code:
--AAA-AAAAAAA---------AA-
AAA------AAAAAAAAAAAAAA
------A----AAAA-----A-------

Using awk, I would need to replace only the "-" located between the last letter and the end of the string by "~"

in order to get:
Code:
--AAA-AAAAAAA---------AA~
AAA------AAAAAAAAAAAAAA
------A----AAAA-----A~~~~~~~

I tried tio use gsub but it replace all the target "-" by only one "~" and doesn't conserve the number of replaced "-".

Thanks for your help ! Smilie
# 2  
Old 01-18-2013
Try:
Code:
awk '
{       if(match($0, /[-]+$/)) {
                t = substr($0, RSTART)
                gsub(/[-]/, "~", t)
                printf("%s%s\n", substr($0, 1, RSTART - 1), t)
        } else  print
}' input

If you are using a Solaris/Sun OS system, use /usr/xpg4/bin/awk or nawk, instead of awk.
This User Gave Thanks to Don Cragun For This Post:
beca123456
# 3  
Old 01-18-2013
Great ! Works perfectly, thanks Don Cragun !

---------- Post updated at 03:27 AM ---------- Previous update was at 02:40 AM ----------

I have another similar question.

input:
Code:
12345
123456789
1234567

How could I add n number of "~" at the end of the strings to have all the strings of the list with the same length (the longest string of the list being the "reference" string).

output:
Code:
12345~~~~
123456789
1234567~~

I tried something like that but the number of "-" being repeated doesn't work in the end section:
Code:
BEGIN{FS=OFS=""; max=0}

{
	if(NF>max){
		max=NF
	}
}

END{print $0 FS "~"{(max-NF)}

}
# 4  
Old 01-18-2013
Code:
echo "12345
123456789
1234" | awk '{printf "%-9s\n", $1}' | sed 's/ /-/g'

try this Smilie
# 5  
Old 01-18-2013
Try:
Code:
awk '
NR == 1{M = m = length($0)}
{       a[NR] = $0
        if(length($0) > M) M = length($0)
        if(length($0) < m) m = length($0)
}
END{    for(i = m; i <= M; i++) fill = fill "~"
        for(i = 1; i <= NR; i++)
                printf("%s%.*s\n", a[i], M - length(a[i]), fill)
}' input

Note also that using "" as the field separator is not portable. It does what you want on some systems, produces strange results on others, and gives errors on others.
Last edited by Don Cragun; 01-18-2013 at 05:02 AM.. Reason: Add note about using an empty string as a field separator.
This User Gave Thanks to Don Cragun For This Post:
PikK45
# 6  
Old 01-18-2013
Thanks for your help PikK45, unfortunately it doesn't work...

As I am learning awk I am trying to use a full awk command preferably

---------- Post updated at 04:05 AM ---------- Previous update was at 04:01 AM ----------

Thanks again Don Cragun, perfect !
# 7  
Old 01-18-2013
beca: that was a typing mistake

can you try using
Code:
sed 's/ /~/g'

instead of
Code:
sed 's/ /-/g'

 
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