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babbab 01-30-2013 09:29 PM
awk help printing only if element is new in array
 
so far

I could build array using

Code:
name_list[$3] = 1
adding only 3rd column to name_list
how do I print only if element is new in array?

danielbmartin 01-30-2013 09:53 PM
Quote:
Originally Posted by babbab (Post 4881048)
how do I print only if element is new in array?
What characteristic distinguishes New from Old?

Daniel B. Martin

babbab 01-30-2013 10:02 PM
say data is..

Code:
aaa 123
bbb 456
bbb 789
ccc 101112
ccc 131415
....
so

Code:
name_list[$1] = 1

now array contains
namelist["aaa"] = 1
namelist["bbb"] = 1
namelist["ccc"] = 1
my intention is to print out only non-duplicated at certain column records.
it should only print out first 1st column encountered data

so desired output is..

Code:
aaa 123
bbb 456
ccc 101112

babbab 01-30-2013 10:17 PM
hmmm

this code actually worked for that matter

Code:
if (name_list[$3] == 0){
    #print code
}
name_list[$3] = 1
thanks for reading my post!!!

grail 01-31-2013 06:44 AM
Using your example:
Code:
awk '!_[$1]++' file

David the H. 01-31-2013 04:17 PM
And in case you're wondering how grail's line works, it's basically entry #43 here:

http://www.catonmat.net/blog/awk-one...ined-part-two/


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