Sed/awk to find negative numbers and replace with 1?

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Sed/awk to find negative numbers and replace with 1?

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04-10-2014

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Sed/awk to find negative numbers and replace with 1?

Greetings. I have a three column file, and there are some numbers in the second column that are <1. However I need all numbers to be positive, thus need to replace all those numbers with just one. I feel like there must be a simple way to use awk to find these numbers and sed to replace but can't make it work.

Input:

Code:

3.894672	4221	4232
79.974159	-63	76
26.139051	1786	1798
30.866007	5045	5055
42.381535	-199	205
17.103092	-953	961
29.135157	1365	1384
29.135157	1643	1658

Desired Output:

Code:

3.894672	4221	4232
79.974159	1	76
26.139051	1786	1798
30.866007	5045	5055
42.381535	1	205
17.103092	1	961
29.135157	1365	1384
29.135157	1643	1658

Thanks!

Twinklefingers

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04-10-2014

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Code:

awk '{$2=($2<0)?1:$2}1' myFile
OR
sed 's/-[0-9][0-9]*/1/'  myFile

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This works like a charm, except that it takes a tab-delimited file and returns a space-delimited file. My fault for not mentioning it in the original post.

Twinklefingers

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OFS variable you have to use like below

Code:

awk '{$2=($2<0)?1:$2}1' OFS='\t' myfile

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04-10-2014

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Quote:

Originally Posted by Twinklefingers

This works like a charm, except that it takes a tab-delimited file and returns a space-delimited file. My fault for not mentioning it in the original post.

Code:

awk '{$2=($2<0)?1:$2}1' OFS=='\t'  myFile

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Variations of vgersh99's solution which don't rebuild $0 when $2 is non-negative:

Code:

awk '$2>=0 || ($2=1)' OFS='\t' myFile

or

Code:

awk '$2<0 {$2=1} 1' OFS='\t' myFile

Regards,
Alister

Last edited by alister; 04-10-2014 at 04:52 PM..

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