Shell Programming and Scripting

Hi,

I am new to this forum and my script skills are very weak.

I have this file (file 1) that contains 3 columns (tab delimited):

kyle start stop
john start stop
joe start stop

And I want to replace name (column 1) from another file. This other file has two columns, one is the match (column 1) and the other column is what I want to substitute into file 1.

kyle bob
john jack
joe arnold

So the output file would look like this:

bob start stop
jack start stop
arnold start stop


Could some give me a solution and a simple explanation. Any help would be fine I tried finding a similar thread but it looks like my case is unique.

Thanks

Everybody belive that but is not.
Anyway try awk

Code:

awk 'NR==FNR{_[$1]=$2;next}$1 in _{$1=_[$1]}1' OFS='\t' file2 file1 > file3

..and now that you have the solution you can search the forum for similar problems.

this is not awk but alternative solution using Python

Code:

#/usr/bin/env python
d={}
for line in open("file1"):
    line=line.strip().split()
    d[line[0]]=line[-1]
for line in open("file"):
    line=line.strip().split()
    print d[line[0]],' '.join(line[1:])

output:

Code:

# ./test.py
bob start stop
jack start stop
arnold start stop

hi danmero, i have the same problem, but i have delimiters as | and I have to replace 41st field in file1 with 2nd field from file2. since i do not understand much awk, i cant change your command to my need. Will you be able to help me out here.

danmero, i used the following version of your commands and it works. Do tell me if you think there might be an issue with this. Also i m yet to test it with my production which is more than 600 MB in size.

nawk -F'|' 'NR==FNR{_[$1]=$2;next}$41 in _{$41=_[$41]}1' OFS='|' file2 file1 > file3

Thanks.