A variable inside an another variable

Question

I have these variables

a1=0.017
a2=0.2
a3=10.7
a4=20.9
a5=35.4

for ((x=1; x<=5; x++))
do
 for i in a${x}
 do
 echo "Welcome $i times"
 done
done

The output must be:

"Welcome 0.017 times"
"Welcome 0.2 times"
"Welcome 10.7 times"
"Welcome 20.9 times"
"Welcome 35.4 times"

But my output now is

Welcome a1 times
Welcome a2 times
Welcome a3 times
Welcome a4 times
Welcome a5 times

How cam I print a1 as $a1 in the way to have "10" ?

Otherwise I have to do this:

for i in $a1 $a2 $a3 $a4 $a5
do
 echo "Welcome $i times"
done

The problem is that I have more than 100 "a" variables and I can not use the last option above

Are good also new suggestion outside of "loops"

Many thanks

Answer 1

It’s not hard to accomplish what you asked for:

a1=0.017
a2=0.2
a3=10.7
a4=20.9
a5=35.4

for ((x = 1; x <= 5; x++)); do
    var="a${x}"
    echo "Welcome ${!var} times"
done

It would have been simpler to make a an array variable, though:

a=(
    0.017
    0.2
    10.7
    20.9
    35.4
)

for x in "${a[@]}"; do
    echo "Welcome ${x} times"
done