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Shell Programming and Scripting

How to quickly show Nth line from the file

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# 1  
Old 02-14-2008
How to quickly show Nth line from the file
Hi all,

How can I quickly show Nth line from the huge file(at least more than 15GB)? I used the following script but seems slower.

See 2717298 th line.

Code:
head -2717298 data0802.dat | tail -1


Thank you very much
# 2  
Old 02-14-2008
You're going to need to read the file until line 2717298 and that will take some time. But try:

sed -n '2717298{p;q;}' datafile
# 3  
Old 02-14-2008
Code:
 sed 'NUMBERq;d' file

.. where NUMBER is the line number you want displayed
# 4  
Old 02-14-2008
Bug
Thank you very much

Smilie
# 5  
Old 02-15-2008
for large files , use awk
Code:
# wc -l file
9812605 file
# time sed -n '2717298{p;q;}' file
2717298 this is a line

real    0m9.412s
user    0m9.313s
sys     0m0.080s
# time sed '2717298q;d' file
2717298 this is a line

real    0m9.595s
user    0m9.329s
sys     0m0.052s
# time awk 'NR==2717298{print;exit}' file
2717298 this is a line

real    0m1.227s
user    0m1.148s
sys     0m0.072s
# time sed -n '2717298{p;q;}' file
2717298 this is a line

real    0m9.616s
user    0m9.429s
sys     0m0.080s
# time sed '2717298q;d' file
2717298 this is a line

real    0m9.105s
user    0m9.005s
sys     0m0.084s
# time awk 'NR==2717298{print;exit}' file
2717298 this is a line

real    0m1.247s
user    0m1.164s
sys     0m0.080s

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