About the script writing

[eric_204]

I have the following report on the shell , how can I cut the field of last two columns and rows ( 49 , 50 , 59 , 60 ) and paste it to other file ? thx

#vi system1.txt
01 02 03 04 05 06 07 08 09 10
11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30
31 32 33 34 35 36 37 38 39 40
41 42 43 44 45 46 47 48 49 50
51 52 53 54 55 56 57 58 59 60

[Stuart Browne]

awk is your friend.

awk 'END {
printf( "%s, %s, %s, %s\n", PrevOne, PrevTwo, LastOne, LastTwo );
}
{
PrevOne = LastOne;
PrevTwo = LastTwo;
LastOne = $(NF - 1);
LastTwo = $(NF);
}' < system1.txt

Not the most neat/elegant, but it works.

[eric_204]

can I simply use the "cut" comamand ? thx

[Stuart Browne]

You possibly could, if it was always a fixed number of fields, and a fixed number of lines, in combination with 'tail'.

tail --lines=2 system1.txt | cut -f9-10

would be close, but not in the format listed above.

[Huc_1]

Very neat..!
had been trying my hand at it when you can out with it...

J-P (0 point for this just a comment, thanks.)

[Mark Grant]

Actually, that last cut thing doesn't work on Linux. At least not in my version of cut because the defaukt delimiter is a tab.

tail -2 system1.txt | cut -d " " -f 9-10

works for me though.

[eric_204]

thx all reply , another question ,
how can i cut this characters "49,50,59,60" from the file "a.txt" and then paste it to another file "b.txt" in a specific position ? thx

$vi b.txt
<----------blank---------->
<--blank->49 50<--blank--->
<--blank->59 60<--blank--->

[Mark Grant]

eric,

I think we are now moving away from the realm of one liners :)

Could you be a bit more specific about where in the second file you want the number to appear.

[eric_204]

hi Mark ,

I just want the characters paste to the third column ( leave the first two column blank ) , how to do it ? thx.

[Mark Grant]

This works, though it might be better to put it in a script of it's own rather than just running it from the command line

tail -2 a.txt | cut -d " " -f 9-10 | {
echo
while read a
do
echo " $a"
done
echo
} > b.txt