nice code, but:

remove call to sum() out of the loop !

e.g. 
my $sum_x = Sum(@x);

$xy_res[$i] = abs($y[$i] - ($sum_y/$n))*abs($x[$i] - ($sum_x/$n));

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In reply to Re^2: Least Squares in Perl by Anonymous Monk
in thread Least Squares in Perl by Anonymous Monk

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