问Perl -使用'my‘声明的变量，仍然出现错误

EN

Global symbol "@Z" requires explicit package name 
(did you forget to declare "my @Z"?) at 
C:/Users/owner/Documents/Slic3r/lib/Slic3r/Print/SupportMaterial.pm line 937. Global symbol "@Z" requires explicit package name (did you forget to declare "my @Z"?) at C:/Users/owner/Documents/Slic3r/lib/Slic3r/Print/SupportMaterial.pm line 945

my ($X_ref,$Y_ref)=grid($min_X,$max_X,$min_Y,$max_Y,$distance);my @X=@$X_ref;my @Y=@{$Y_ref};
for my $i (0..$#X){
    $Z[$i]=20;#The function that defined the height of each point. This setting wil give you a flat roof. For a more advanced tree, try:
    #$Z[$i]=-0.01*$X[$i]**2+0.2*$Y[$i]-0.005*$Y[$i]**2+20;
}

#End of input parameters.

my $min_radian = deg2rad($min_angle);
my $b = tan($min_radian);
my @Z=map{$_/$b} @Z;

"my" variable @Z masks earlier declaration in same statement at C:/Users/owner/Documents/Slic3r/lib/Slic3r/Print/SupportMaterial.pm line 945.
"my" variable @Z masks earlier declaration in same statement at C:/Users/owner/Documents/Slic3r/lib/Slic3r/Print/SupportMaterial.pm line 945.
syntax error at C:/Users/owner/Documents/Slic3r/lib/Slic3r/Print/SupportMaterial.pm line 937, near "$Z["

my ($X_ref,$Y_ref)=grid($min_X,$max_X,$min_Y,$max_Y,$distance);my @X=@$X_ref;my @Y=@{$Y_ref};
for my $i (0..$#X){
    my $Z[$i]=20;#The function that defined the height of each point. This setting wil give you a flat roof. For a more advanced tree, try:
    #$Z[$i]=-0.01*$X[$i]**2+0.2*$Y[$i]-0.005*$Y[$i]**2+20;
}

#End of input parameters.

my $min_radian = deg2rad($min_angle);
my $b = tan($min_radian);
my @Z=map{$_/$b} my @Z;