$ perl slope5.pl
Can't use string ("4.3125") as an ARRAY ref while "strict refs" in use at ../utils1.pm line 39.
$ cat slope5.pl
#!/usr/bin/perl -w
use strict;
use 5.010;
use Math::Trig;
BEGIN { push @INC, ".."; }
use utils1;

my @AoA;
my $aoa_ref = \@AoA;
my @vector = (4.3125, 0.4375);
push @AoA, @vector;
@vector = (4.375, 0.375);
push @AoA, @vector;
@vector = (4.4375, 0.375);
print_aoa($aoa_ref);
__END__ 
$