If your arrays are small go with one of the many grep/map/slice answers offered, but be aware that for large arrays they will create two or more huge intermediate lists that consume substantial amounts of memory, and thus time.

The alternative that avoids those huge stack allocations only requires a single temporary scalar and runs very efficiently: 

@a=(6,7,8); 
@b=(3,2,1);;

$i=0; 
$b[$_] > 1 and $c[ $i++ ] = $a[$_] for 0 .. $#a;;

print @c;;
6 7

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In reply to Re: Boolean array indexing by BrowserUk
in thread Boolean array indexing by johnmillerflorida

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