My script is setting array from grep results in such a way that empty grep results are also being stored in array.
Eg.
set -x echo "${Arr[@]}" + echo '' 'word' '' 'word2' Can someone help unset those empty values so that echo "${#Arr[@]}" gives 2 instead of 4
Tried
var=-1 && for i in "${Input_Arr[@]}"; do var=$((var+1)); if [ -z "$i" ]; then unset "${Input_Arr[$var]}"; fi; done But it isn't working
First, there's no need to invent a dummy index - you can access the array's indices using the indirection operator !
Second, "${Input_Arr[$var]}" is the element's value; unset needs the element's name, Input_Arr[$var] or just Input_Arr[var], since it's already an arithmetic context). So given:
$ arr=(foo '' bar '' baz) $ declare -p arr declare -a arr=([0]="foo" [1]="" [2]="bar" [3]="" [4]="baz") then
$ for i in ${!arr[@]}; do [[ -z ${arr[i]} ]] && unset arr[i]; done leaves
$ declare -p arr declare -a arr=([0]="foo" [2]="bar" [4]="baz") This also works for associative arrays - with suitable adjustments for the non-numeric keys (including double quoting expansions to prevent potential split + glob):
$ declare -A Arr=(['1st val']=foo ['2nd val']='' ['3rd val']=bar ['4th val']='' ['5th val']=baz) $ declare -p Arr declare -A Arr=(["5th val"]="baz" ["2nd val"]="" ["4th val"]="" ["3rd val"]="bar" ["1st val"]="foo" ) $ for i in "${!Arr[@]}"; do [[ -z ${Arr[$i]} ]] && unset Arr["$i"]; done $ declare -p Arr declare -A Arr=(["5th val"]="baz" ["3rd val"]="bar" ["1st val"]="foo" ) 
If you want the remaining array elements to be collapsed to consecutive indexes starting from zero, it's probably easiest to make a copy of the array:
arr1=(foo '' bar '') arr2=() for val in "${arr1[@]}"; do [[ $val ]] && arr2+=( "$val" ) done That would leave arr2 as declare -a arr2=([0]="foo" [1]="bar"), i.e. the index of bar was changed from 2 to 1 to avoid leaving a hole.
You could also do that in-place by just copying the individual elements and unsetting the last ones, but it's more manual work.
