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Help with awk, where line length and field position are variable


 
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# 1  
Old 08-30-2013
Help with awk, where line length and field position are variable

I have several questions about using awk. I'm hoping someone could lend me a hand. (I'm also hoping that my questions make sense.)

I have a file that contains pipe separated data. Each line has similar data but the number of fields and the field position on each line is variable.
Code:
cheese64@server$ cat file.txt 

1234567890|bbb|ccc|ddd|eee|fff|ggg|hhh|iii|jjj|kkk|lll 
1234567890|bbb|ccc|ddd|eee|hhh|iii|jjj|kkk|lll

Using the example above, I need to extract specific data from the following fields. (Shown below.) I'm struggling because the data on each line could be in a different position.

Code:
1234567890|bbb|ccc|eee|jjj|kkk|lll

Running a command like this works on the first line but not the second.
Code:
awk '{FS="|"} {print $2"|"$3"|"$5"|"$9"|"$10"|"$11}' file.txt

What's the best way for me to extract data for these fields?

Next, how can I print everything from x-field to the end of the line, when the number of fields is unknown (fields 9, 10 and 11, as an example). I'm sure there's a better way to get the last three fields, for example, without enumerating each field.

The following awk command gives me everything from $6 on but will also print $1-$5 again.
Code:
awk '{FS="|"} {print $2"|"$3"|"$5"|"$NF}' file.txt

Lastly, is there a way to print part of a field, followed by other fields? Using the example above, I'd like to print the following:

Code:
123456|bbb|ccc|ddd|eee|fff|ggg|hhh|iii|jjj|kkk|lll

How can I cut the last four digits from the first field and continue to print the rest of the fields?

Thanks for the help -
# 2  
Old 08-30-2013
Hello,

Could you please try following code. It should help you.


Code:
awk -F "|" ' {v=""} {$6=$7=v} 1' data_new | sed 's/[[:space:]][[:space:]]//g; s/[[:space:]]/\|/g'


Output will nbe as follows.


Code:
1234567890|bbb|ccc|ddd|eee|hhh|iii|jjj|kkk|lll



Thanks,
R. Singh
# 3  
Old 08-30-2013
the NF variable is the number of fields in current record. You seem to require $1"|"$2"|"$3"|"$4"|"$5"|"$(NF -4)"|"$(NF -3)"|"$(NF -1)"|"$(NF -1)"|"$NF
# 4  
Old 08-30-2013
Try this (partly stolen from scynesaver):
Code:
awk -F\| '{sub (/....$/,"",$1); print $1, $2, $3, $4, $5, $6, $(NF-4), $(NF-3), $(NF-2), $(NF-1), $NF}' OFS=\| file
123456|bbb|ccc|ddd|eee|fff|hhh|iii|jjj|kkk|lll 
123456|bbb|ccc|ddd|eee|hhh|hhh|iii|jjj|kkk|lll

 

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