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Delete line with sed or awk (with specified condition)

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# 1  
Old 01-17-2011
Delete line with sed or awk (with specified condition)
Hello. I'm trying to delete the lines of a file does not contain the letter "T " (for example) at position 26.

So far, I could only print the result:
Code:
awk '{if (substr ($ 1,1,26)! ~ / T /) print}' file.txt

How I can do to eliminate the lines that meet this condition?


Help please. Thanks.
Last edited by Franklin52; 01-18-2011 at 03:17 AM.. Reason: Please use code tags
# 2  
Old 01-17-2011
There are many many ways you could to this. With grep, for instace:
Code:
grep -v '^.........................T' inputfile

(there should be 25 ".")

With awk, I'd:
Code:
awk 'substr($0, 26, 1) != "T"' inputfile

I am sure others will come up with different methods.
Last edited by m.d.ludwig; 01-17-2011 at 04:00 PM.. Reason: missing space
This User Gave Thanks to m.d.ludwig For This Post:
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# 3  
Old 01-17-2011
ready. I have it.
# 4  
Old 01-17-2011
Code:
# sed '/^.\{25\}\(T\).*/d' infile

# 5  
Old 01-17-2011
Quote:
delete the lines of a file does not contain the letter "T "
That means print the lines that do, doesn't it?
Code:
awk '$26=="T"' FS= file.txt

Code:
sed '/.\{25\}T/!d' file.txt

Code:
grep '.\{25\}T' file.txt

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