use mapcar;

sub a_add  { $v1 = [ mapcar { $_[0] + $_[1] } @_[0,1] ] }
sub a_subt { $v1 = [ mapcar { $_[0] - $_[1] } @_[0,1] ] }
sub a_mult { $v1 = [ mapcar { $_[0] * $_[1] } @_[0,1] ] }
sub a_div  { $v1 = [ mapcar { $_[1] ? $_[0] / $_[1] : undef } @_[0,1] 
+] }
[download]

------
We are the carpenters and bricklayers of the Information Age.

Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.

One could, if one had mapcar.

However, search.cpan.org does not admit to its existence...
--
Mike (Edit: OOPS! mapcar module. Nice!)

Well, if you wanted to admit modules, you could have some fun with the PDL module:

    #!/usr/bin/perl -w
    use strict;
    use PDL;

    my $v1 = pdl reverse 1..10;
    my $v2 = pdl 0..9;
    my $v3 = pdl ((2)x10);

    my $add  = $v1 + $v2;
    my $mult = $v1 * $add;
    my $div  = $mult / $v3;
    my $sub  = $div - $v1;

    print "add:  $add\nmult: $mult\ndiv:  $div\nsub:  $sub\n";

    # we didn't stomp the original vectors either...
    # and of course, we can work with matrices too

    my $matA = pdl [0,0,0],[1,1,1],[2,2,2]; # 2d 3x3
    $matA++;         # add one across the board
    $matA *= 2;      # and scale up by factor of 2
    print "A: $matA\n";
    $matA *= $matA;  # scale it by itself
    print "B: $matA\n";
    $matA x= $matA;  # matrix multiply
    print "C: $matA\n";

    # and say, did you ever want to know the eigenvalues and
    # eigenvectors of a 4 x 4 matrix of a fibonacci sequence???

    use PDL::Slatec;           # Fortran never dies :-)
    my $fibo = fibonacci(4,4);
    my($eigvals, $eigvecs) = eigsys($fibo);
    print <<EOF;
    Fibo matrix: $fibo
    Eigenvalues: $eigvals
    Eigenvectors:$eigvecs
    EOF
    __END__


    add:  [10 10 10 10 10 10 10 10 10 10]
    mult: [100 90 80 70 60 50 40 30 20 10]
    div:  [50 45 40 35 30 25 20 15 10 5]
    sub:  [40 36 32 28 24 20 16 12 8 4]
    A: 
    [
     [2 2 2]
     [4 4 4]
     [6 6 6]
    ]

    B: 
    [
     [ 4  4  4]
     [16 16 16]
     [36 36 36]
    ]

    C: 
    [
     [ 224  224  224]
     [ 896  896  896]
     [2016 2016 2016]
    ]

    Fibo matrix: 
    [
     [  1   1   2   3]
     [  5   8  13  21]
     [ 34  55  89 144]
     [233 377 610 987]
    ]

    Eigenvalues: [0.859383 6.05138 68.0353 1010.05]
    Eigenvectors:
    [
     [    0.99101    -0.13375 -0.00326739  0.00031052]
     [  -0.131501    -0.97827    0.160279 -0.00218367]
     [ -0.0244236   -0.156787   -0.974861    0.156421]
     [  0.0032657   0.0227098    0.154745    0.987688]
    ]
[download]

Module-less, one could still use just plain boring map:

sub amult {
  my ($a, $b) = @_;
  croak "Arrays of different sizes" unless $#$a==$#$b;
  map { $a->[$_] * $b->[$_] } (0..$#$a)
}
[download]

Sorry, but your wheel has already been invented.

$_ += 123 for @foo;
$_ -= 123 for @foo;
$_ *= 123 for @foo;
$_ /= 123 for @foo;
[download]

@foo ^+= 123;
@foo ^-= 123;
@foo ^*= 123;
@foo ^/= 123;
[download]

@foo ^+= @bar;
etcetera
[download]

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W5kIHBhY2soKS4gQnV0IGRvIHlvdS
ByZWNvZ25pc2UgQmFzZTY0IHdoZW4
geW91IHNlZSBpdD8gIC0tIEp1ZXJk