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Replacing values into a single column. sed/PERL

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# 1  
Old 09-23-2014
Replacing values into a single column. sed/PERL
Hello everyone,
i need to replace in the second column of my csv file, points by nothing and dash by comma like this:

Input:
Code:
1 2 1;12.111.312-2;1.2;2;1-3
2 1 1;11.212.331-1;3.3;1;2-2

Output:
Code:
1 2 1;12111312;2;1.2;2;1-3
2 1 1;11212331;1;3.3;1;2-2

SED or PERL commands preferably.

Thanks!
# 2  
Old 09-23-2014
You said you wanted "-" in field 2 to be replaced by ","; but your sample output used ";" instead of ",". Which do you really want?

What have you tried?

Why are sed and perl preferable to awk for this?
# 3  
Old 09-23-2014
in fact i want to replace "-" by semicolon instead simple comma (Mea culpa)
I prefer sed or perl because after some experiences i have seen that sed or perl commands was more fast than awk...
# 4  
Old 09-23-2014
And, what have you tried?
# 5  
Old 09-23-2014
I assume he doesn't know where to start Smilie
Code:
# accurate and fast (recommended)
awk -F";" '{gsub(/\./,"",$2); sub(/-/,";",$2); print}' OFS=";" input

Code:
# accurate, but relatively slow
perl -e 'while(<>){ @f=split(/;/); $f[1]=~s/\.//g; $f[1]=~s/-/;/; print join(";",@f); }' input

Code:
# very fast, but it doesn't care for columns, it simply deletes the first two occurrences of "."
# and replaces the first ocurrence of "-" with ";". It might work for you, if there are no "."s
# and no "-" in the first column PLUS if there are always two "."s and one "-" in the second column.
sed 's/\.//;s/\.//;s/-/;/' input

# 6  
Old 09-24-2014
i cant select just the 2nd column. To replace its easy with
Code:
sed -i

command but i can do that for the whole file. To remove points, i can use
Code:
grep -Ev

, but how select just the 2nd column to do these changes.

Thanks

Julien
# 7  
Old 09-24-2014
I prefer using awk (as suggested by junior-helper) because it is easy for me to read and immediately understand. I believe the following sed script also does what you want, but for many users this is less readable and harder to understand:
Code:
sed '
:again
/^\([^;]*;[^.;]*\)[.]/s//\1/
t again
/^\([^;]*;[^-;]*\)-/s//\1;/
' Input

Fast is nice; but I'm not sure that sed is going to be any faster than awk for this. Which script do you find easier to understand?
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