compare files and calculating

[tonivm]

Hi everybody:
Could anybody tell me how can I do this.
I've two files (file1 & file2) where file1 its last row it has first field value equal that the first row in file2, thyen I want calculate the difference in other fields, and this values apply in file2. This is:

file1:
.............................
.............................
10.87 228.983
14.31 211.306
19.83 214.468

file2 :
19.83 217.83
28.67 231.34
42.74 264.576
.............................
.............................

Then diff=$2(file2)-$2(file1)=217.83-214.468=3.362, then I would like to have this output:
19.83 214.468
28.67 231.34-diff
42.74 264.576-diff
.............................
.............................

This is:
19.83 214.468
28.67 227.978
42.74 261.214
.............................
.............................


Thanks in advance and cheers.

 

[PHV]

And what have you tried so far ?
Tip: sometimes FNR is not the same as NR

Hope This Helps, PH.
Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884 or FAQ181-2886

 

[tonivm]

I tried this:

tail -1 file1 | read x y z
head -1 file2 | read a b c
if [ $a -eq $x ]
then
awk -v var1=$b -v var2=$y ' BEGIN { dif=var1 - var2 } { print $1 , ( $2 - dif ) } ' file2 > file3
fi

But I have:

19.83 217.83
28.67 231.34
42.74 264.576
65 232.5
100 210

and the second column does not correspond about I wish.

 

[PHV]

Are you aware that a single awk program may process many input files ?

Hope This Helps, PH.
Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884 or FAQ181-2886

 

[tonivm]

Hi PHV:
Really I'm not sure. But I wonder that before use awk, if I save this:

sound=(`tail -1 05080300.ddr`);
declare -a bcn;
bcn=(`head -1 mls_65.tmp1`);
declare -a sound;

after I can use it into awk script.