BASH > faire des calculs mathématiques

a=1 ; b=17 ; bc <<< "$a*100/$b"

 

 

var3=`bc <<< "scale=2; $var2"`

On the other hand, $var1 and $var2 won’t store float (bash doesn’t manage them), so you bc instead.

diff=$(($epoc2-$epoc1))
var1=$(bc <<< "scale=3 ; $diff / 60")
var2=$(bc <<< "scale=3 ; $var1 / 57")
var3=$(bc <<< "scale=2; $var2")

 

 

bc <<< 'scale=2; 100/3'
33.33

UPDATE 20130926 : you can use:

bc -l <<< '100/3' # saves a few hits
33.33333333333333333333