/**
* @param array $gradient
* @param array $coefficients
* @return bool
*/
public function converged(array $gradient, array $coefficients) : bool
{
$steppedGradient = [];
foreach ($gradient as $i => $slope) {
$steppedGradient[] = $this->schedule->step($i) * $slope;
}
return $this->criteria->converged($steppedGradient, $coefficients);
}
/**
* @param Observations $observations
* @return array
*/
public final function regress(Observations $observations) : array
{
$coefficients = array_fill(0, $observations->getFeatureCount(), 0.0);
do {
$gradient = $this->calculateGradient($observations, $coefficients);
$this->schedule->update($gradient);
$coefficients = $this->updateCoefficients($coefficients, $gradient);
} while (!$this->stoppingCriteria->converged($gradient, $coefficients));
return $coefficients;
}