in reply to count the occurrences of particular word in a file and extract number in ()

  1. how to I count the occurrences of word 'the' in a file? 
    open my $fh, '<', 'theFile' or die $!;

my $count = 0;
while( <$fh> ) {
    ++$count while m[the]g;
}
print "'the' appeared $count times in 'theFile'";

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  2. how to I extract the numeric values in a () sample code:? $extract =~/^\( (\d.+) \)$/
    if( $extract =~/^\( (\d.+) \)$/ ) {
    print "The number was $1";
}
else {
    print "The regex didn't match";
}

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

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Re^2: count the occurrences of particular word in a file and extract number in ()
by NetWallah (Canon) on Mar 20, 2011 at 05:22 UTC
    Um -- (1) would be an infinite loop, without a "g" in the regex. Use: 
    use strict;

my $count = 0;
while( <DATA> ) {
   print;
    ++$count while m[the]ig;
}
print "'the' appeared $count times in 'theFile'\n";
__DATA__
THis is the dawning of the age of Aquarius.
Good morning Starshine, the earth says hello. The end.

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    For #2, simpler code: 
    my ($extracted_value) = $extract =~/^\( (\d.+) \)$/;
# Will be undef if nothing found.

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         Syntactic sugar causes cancer of the semicolon.        --Alan Perlis

[reply]
[d/l]
[select]
      (1) would be an infinite loop, without a "g" in the regex

      Indeed, now corrected. I explicitly remove the /i (and accidentally the /g), because it would give wrong results if the OP really mean 'the' and not 'The' or 'THE'.

      simpler code: Will be undef if nothing found.

      That is no simpler as you still have to handle the possibility of undef.

      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.
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