How can I get unique values from an array in Bash?

Question

I\'ve got almost the same question as here.

I have an array which contains aa ab aa ac aa ad, etc. Now I want to select all unique elements from this ar

Answer 1

'sort' can be used to order the output of a for-loop:

for i in ${ids[@]}; do echo $i; done | sort

and eliminate duplicates with "-u":

for i in ${ids[@]}; do echo $i; done | sort -u

Finally you can just overwrite your array with the unique elements:

ids=( `for i in ${ids[@]}; do echo $i; done | sort -u` )