Dear Monks,

I have a subroutine like: 


sub correlation {

  print "\nWe are in the correlation subroutine\n\n";

  my ($x_ref, $y_ref) = @_;     

  
  
  my @x = @{$x_ref};

  my @y = @{$y_ref}; 


  my $lfit = Statistics::LineFit->new();
  $lfit->setData(@x, @y);
  
  printf "a=%.4f, b=%.4f,  R2=%.4f\n", $lfit->coefficients(), $lfit->r
+Squared();
  
  
  return  "a=%.4f, b=%.4f, R2=%.4f\n", $lfit->coefficients(), $lfit->r
+Squared();

}

[download]
This sub is activated like: 

my ($y_axis_intercept, $gradient, $R2) = correlation(\@primarys, \@sec
+ondarys);

[download]
The error message that I get is: 

Can't use an undefined value as an ARRAY reference at c:/Perl/site/lib
+/Statistic
s/LineFit.pm line 191, <DATA> line 164.

[download]

In reply to LineFit.pm error due to undef value by Win

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