modify("+$preset_years years");
}
} else {
try {
$start_date = new DateTime($start_date_input);
$end_date = new DateTime($end_date_input);
if ($start_date >= $end_date) {
$errors[] = "Das Enddatum muss nach dem Startdatum liegen.";
}
} catch (Exception $e) {
$errors[] = "Ungültiges Datumsformat. Bitte verwenden Sie das Format JJJJ-MM-TT.";
}
}
if (empty($errors)) {
$interval = $start_date->diff($end_date);
$days = $interval->days;
// Simple interest calculation (adjust as needed for compound interest)
$annual_interest = ($principal_amount * $interest_rate) / 100;
$calculated_interest = ($annual_interest / 365) * $days;
$final_amount = $principal_amount + $calculated_interest;
echo '
';
echo '
Ergebnis:
';
echo '
Kapital: ' . number_format($principal_amount, 2, ',', '.') . ' €
';
echo '
Zinssatz: ' . number_format($interest_rate, 2, ',', '.') . ' %
';
echo '
Anlagedauer: ' . $days . ' Tage
';
echo '
Berechnete Zinsen: ' . number_format($calculated_interest, 2, ',', '.') . ' €
';
echo '
Endbetrag: ' . number_format($final_amount, 2, ',', '.') . ' €
';
echo '