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Grep -v, with -A or -B?


 
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# 8  
Old 10-24-2009
Haha. Sorry I completely missed the point Smilie Hang on!
# 9  
Old 10-24-2009
lol, it's ok, at least you understand what i mean now, sorry for not being clear in what i was trying to accomplish
# 10  
Old 10-24-2009
Code:
awk -v A=-1 '/figure/ { A = 1 } A-- >= 0 {next } 1' file1

Change A = 1 to another number depending on how many lines you want to skip.

(still looking at grep option!)
# 11  
Old 10-24-2009
Quote:
Originally Posted by scottn
Code:
awk -v A=-1 '/figure/ { A = 1 } A-- >= 0 {next } 1' file1

Change A = 1 to another number depending on how many lines you want to skip.

(still looking at grep option!)
awk?, i've never heard of this command, however it gets the job done, i'll look into it more, thanks for the help
# 12  
Old 10-24-2009
It seems to me grep is working as intended. The example is:

Code:
$> grep -v -A 1 'figure' test
This is a test of grep
to see how inversion really works
and figure out the problem that the class is having
hopefully this works

But this expected behavior if we take a look at the same command without the -A option:
Code:
$> grep -v 'figure' test
This is a test of grep
to see how inversion really works
hopefully this works

So the -A option works correctly since the line "and figure out ..." gets printed as a context to the second matched line.

If we take an example where only the first line gets output:
Code:
$> grep -v l test
This is a test of grep

With -A the result becomes:
Code:
$> grep -v l -A 1 test
This is a test of grep
to see how inversion really works

---------- Post updated at 10:06 AM ---------- Previous update was at 09:17 AM ----------

Actually one has to ask to what question the answer would be:
Code:
and figure out the problem that the class is having
hopefully this works

The question would be:

print any line that does not contain the string "figure" nor follows a line that does contain that string.
 

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