sub

  • namespace: Rindow\NeuralNetworks\Gradient\Func
  • classname: Sub

Differentiable subtraction function.

Methods

add

$builer->sub(
    Variable|NDArray $a,
    Variable|NDArray $b
) : Variable

Create and execute the function in the builder method

Arguments

  • a,b: The arguments are Variable or NDArray. Implicitly create Variable for NDArray.
use Rindow\Math\Matrix\MatrixOperator;
use Rindow\NeuralNetworks\Builder\NeuralNetworks;
$mo = new MatrixOperator();
$nn = new NeuralNetworks($mo);
$g = $nn->gradient();
$a = $g->Variable([1,2]);
$b = $g->Variable([2,3]);
$c = $nn->with($tape=$g->GradientTape(),function() use ($g,$a,$b) {
    return $g->sub($a,$b);
});
[$da,$db] = $tape->gradient($c,[$a,$b]);
echo $mo->toString($c)."\n";
echo $mo->toString($da)."\n";
echo $mo->toString($db)."\n";

# [-1,-1]
# [1,1]
# [-1,-1]