expr ?!


 
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# 1  
Old 09-06-2011
Java expr ?!

Hey there
i want to subtract the content from $b from $a. Each variable has got 18 values (normal numbers from 0 - 99).
How can i subtract them? I know i have to use the expr command, this is what i have till now:

a=`cat Tabelle.dat | awk {'print $4'} | awk -F: {'print $1'}`
b=`cat Tabelle.dat | awk {'print $4'} | awk -F: {'print $2'}`
result=`( expr $a - $b )`
echo "$result"

Example:
content of $a
4
7
13
15
...

content of $b
5
3
6
17

result has to be:
$bla1 - $bla2
4 - 5 = -1
7 - 3 = 4
13 - 6 = 7
15 - 17 = -2
....
I know i have to use a loop but i dont know how to put it in there...
I hope u can help me =)

mfg
Mad van Bert
# 2  
Old 09-06-2011
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