How do I remove duplicate values?

[whatisthis987]

Thanks in advance for any help. What I want...

Input file:
John line1
John line2
John line3
Mary line4
Mary line5
Walter line6
Jack line7
Jack line8

Output file:
John line1
line2
line3
Mary line4
line5
Walter line6
Jack line7
line8


Keep everything in $2 the same. Only remove duplicates in $1.

 

[PHV]

What have you tried so far and where in your code are you stuck ?

Hope This Helps, PH.
FAQ219-2884
FAQ181-2886

 

[whatisthis987]

I tried uniq -u but it returns the same as the input file. This is becuase it compares lines instead of the fields.

 

[PHV]

I'd use awk

Hope This Helps, PH.
FAQ219-2884
FAQ181-2886

 

[whatisthis987]

May I know how would you do it with awk?

 

[whatisthis987]

Nevermind. A simple if loop in Excel does the trick.

 

[Annihilannic]

I would do it something like this:

awk '$1==p {$1=" "} {print; p=$1}' inputfile > outputfile

Annihilannic.