General :: Bash: Calculating In Array And Storing Result In Array?

I have an array called arrayini which stores numbers. I want to take log to the base 2 of each of the numbers in that array and put it in file called result. I've used the following code to do it.

Code:

size=${#arrayini[@]}
for ((i=0;i<size;i++))
do
echo "scale = 12; l(${arrayini[$i]})/l(2)" | bc -l
done >result

It works fine but its taking pretty long to calculate since I've got about 230,000 items in the array. So I decided to store the result into an array hoping that it'd be faster. I tried the following code. arrayresult is where I try and store the result. The code doesn't work because of the second last line.

Code:

unset arrayresult
size=${#arrayini[@]}
for ((i=0;i<size;i++))
do
arrayresult[$i]="scale = 12; l(${arrayini[$i]})/l(2)" | bc -l
done >FILE2

There is a syntax error clearly.