Hi Monks, I have an array 
@array = ("x y.g z 123", "a b.f c 456", "d b.c w 321")

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Each string in @array is always of the same form but with different letters and numbers. If I split the strings by white space, then the important elements are the second ones - ie "y.g", "b.f" and "b.c".

More specifically, what is important is the first component of these strings, ie "y", "b" and "b"

Now I need to filter @array based on these components mentioned above. The filtering is according to another array 

@include = ("b","q")

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so since $array[0] does not contain a "b" or "q" after splitting and looking at the second element it is removed.

I can do this with a series of splits, and testing the components exist in a test hash 


my %testHash = map { $_,1} @include;

foreach my $tmp (@array){
        my @tokens = split /\s+/,$tmp;
         my ($test,$rubbish) = split /\./, $tokens[1];
    push (@keep, $tmp) if (exists $testHash{$test});
}

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But it is very slow when repeated on many different arrays. Is there are more efficient way to use consecutive splitting and a map function? Maybe somebody can see a more elegant way of solving this problem? Many thanks, Chris.

In reply to filter an array with consecutive splits by coldy

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