Conjugate transpose: Difference between revisions

Added a Perl section.
(Restoring visibility of task description formulae hidden by under-tested cosmetic edits of 23:08, 14 August 2016)
(Added a Perl section.)
Line 1,252:
isnormal(M)=my(H=conj(M~));H*M==M*H
isunitary(M)=M*conj(M~)==1</lang>
 
=={{header|Perl}}==
In general, using two or more modules which overload operators can be problematic. For this task, using both Math::Complex and Math::MatrixReal gives us the behavior we want for everything except matrix I/O, i.e. parsing and stringification.
<lang perl>use strict;
use English;
use Math::Complex;
use Math::MatrixReal;
 
my @examples = (example1(), example2(), example3());
foreach my $m (@examples) {
print "Starting matrix:\n", cmat_as_string($m), "\n";
my $m_ct = conjugate_transpose($m);
print "Its conjugate transpose:\n", cmat_as_string($m_ct), "\n";
print "Is Hermitian? ", (cmats_are_equal($m, $m_ct) ? 'TRUE' : 'FALSE'), "\n";
my $product = $m_ct * $m;
print "Is normal? ", (cmats_are_equal($product, $m * $m_ct) ? 'TRUE' : 'FALSE'), "\n";
my $I = identity(($m->dim())[0]);
print "Is unitary? ", (cmats_are_equal($product, $I) ? 'TRUE' : 'FALSE'), "\n";
print "\n";
}
exit 0;
 
sub cmats_are_equal {
my ($m1, $m2) = @ARG;
my $max_norm = 1.0e-7;
return abs($m1 - $m2) < $max_norm; # Math::MatrixReal overloads abs().
}
 
# Note that Math::Complex and Math::MatrixReal both overload '~', for
# complex conjugates and matrix transpositions respectively.
sub conjugate_transpose {
my $m_T = ~ shift;
my $result = $m_T->each(sub {~ $ARG[0]});
return $result;
}
 
sub cmat_as_string {
my $m = shift;
my $n_rows = ($m->dim())[0];
my @row_strings = map { q{[} . join(q{, }, $m->row($ARG)->as_list) . q{]} }
(1 .. $n_rows);
return join("\n", @row_strings);
}
 
sub identity {
my $N = shift;
my $m = new Math::MatrixReal($N, $N);
$m->one();
return $m;
}
 
sub example1 {
my $m = new Math::MatrixReal(2, 2);
$m->assign(1, 1, cplx(3, 0));
$m->assign(1, 2, cplx(2, 1));
$m->assign(2, 1, cplx(2, -1));
$m->assign(2, 2, cplx(1, 0));
return $m;
}
 
sub example2 {
my $m = new Math::MatrixReal(3, 3);
$m->assign(1, 1, cplx(1, 0));
$m->assign(1, 2, cplx(1, 0));
$m->assign(1, 3, cplx(0, 0));
$m->assign(2, 1, cplx(0, 0));
$m->assign(2, 2, cplx(1, 0));
$m->assign(2, 3, cplx(1, 0));
$m->assign(3, 1, cplx(1, 0));
$m->assign(3, 2, cplx(0, 0));
$m->assign(3, 3, cplx(1, 0));
return $m;
}
 
sub example3 {
my $m = new Math::MatrixReal(3, 3);
$m->assign(1, 1, cplx(0.70710677, 0));
$m->assign(1, 2, cplx(0.70710677, 0));
$m->assign(1, 3, cplx(0, 0));
$m->assign(2, 1, cplx(0, -0.70710677));
$m->assign(2, 2, cplx(0, 0.70710677));
$m->assign(2, 3, cplx(0, 0));
$m->assign(3, 1, cplx(0, 0));
$m->assign(3, 2, cplx(0, 0));
$m->assign(3, 3, cplx(0, 1));
return $m;
}</lang>
{{out}}
<pre>
Starting matrix:
[3, 2+i]
[2-i, 1]
Its conjugate transpose:
[3, 2+i]
[2-i, 1]
Is Hermitian? TRUE
Is normal? TRUE
Is unitary? FALSE
 
Starting matrix:
[1, 1, 0]
[0, 1, 1]
[1, 0, 1]
Its conjugate transpose:
[1, 0, 1]
[1, 1, 0]
[0, 1, 1]
Is Hermitian? FALSE
Is normal? TRUE
Is unitary? FALSE
 
Starting matrix:
[0.70710677, 0.70710677, 0]
[-0.70710677i, 0.70710677i, 0]
[0, 0, i]
Its conjugate transpose:
[0.70710677, 0.70710677i, 0]
[0.70710677, -0.70710677i, 0]
[0, 0, -i]
Is Hermitian? FALSE
Is normal? TRUE
Is unitary? TRUE
</pre>
 
=={{header|Perl 6}}==
Anonymous user