Splitting a file from specific column content

Roy Smith roy at panix.com
Sun Jan 22 14:26:29 EST 2012


I stand humbled.

On Jan 22, 2012, at 2:25 PM, Tim Chase wrote:

> On 01/22/12 08:45, Roy Smith wrote:
>> I would do this with standard unix tools:
>> 
>> grep '^[012]' input.txt>  first-three-seconds.txt
>> grep '^[34]' input.txt>  next-two-seconds.txt
>> grep '^[567]' input.txt>  next-three-seconds.txt
>> 
>> Sure, it makes three passes over the data, but for 20 MB of data, you
>> could have the whole job done in less time than it took me to type this.
> 
> 
> If you wanted to do it in one pass using standard unix tools, you can use:
> 
> sed -n -e'/^[0-2]/w first-three.txt' -e'/^[34]/w next-two.txt' -e'/^[5-7]/w next-three.txt'
> 
> -tkc
> 
> 
> 


--
Roy Smith
roy at panix.com






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