I want to write a script that loops through a array and loop will consider current and following values in every round, for example -
VARIABLES=( 10 20 30 40 50 80 )
for i in ${VARIABLES[@]}; do ## Ideally it should stop at 2nd last value
#Value1=$i
#Value2=$(i+1)
done
How to achieve the same in correct way?
I've got few variants, first using function and shift
values=( 10 20 30 40 50 80 )
get_paired_values () {
while [[ $@ ]]; do
value1=$1 value2=$2
echo "$value1 $value2"
shift 2
done
}
get_paired_values "${values[@]}"
And second using while loop over indexes, which is even more elegant)
i=0
while [[ ${values[$i]} ]]; do
value1=${values[$i]} ; ((i++)); value2=${values[$i]}
echo "$value1 $value2"; ((i++))
done
And a variation of second method but using slice and read
i=0
while [[ ${values[$i]} ]]; do
read value1 value2 <<< ${values[@]:$i:2}
echo "$value1 $value2"; ((i+=2))
done
You need to loop through the indexes, not the array elements, so you can do arithmetic with the index.
for ((i=0; i < ${#VARIABLES[@]}-1; i++))
do
value1=${VARIABLES[i]}
value2=${VARIABLES[i+1]}
...
done
