EXPR in shell

pragti · 07-21-2004, 02:24 AM

a2=1
b=2
c=3
expr a$b + 3 --------giving wrong ans
expr `echo \$a$b + 3` ---------giving wrong ans

is giving error how to solve

Vookimedlo · 07-21-2004, 02:35 AM

and what would you like to do?

pragti · 07-21-2004, 02:41 AM

my application need me to add 3 to a variable a?.the variable is dependent on the value of b.i.e if b=7 then i need to add 3 to a7
if b=10 then i need to add 3 to a10

keefaz · 07-21-2004, 03:54 PM

use 3 variables

a=7
b=7
A=

if [ "$b" = 7 ]; then
A=a`expr $a + 3`
fi
echo $A