public ExtDecimal log10(int scale) {
        // Not yet customized
        if (compareTo(ZERO) < 0) {
            throw new ArithmeticException("Logarithm of a negative number in a real context");
        } else if (compareTo(ZERO) == 0) {
            throw new ArithmeticException("Logarithm of 0");
        } else if (compareTo(ONE) == 0) {
            return ZERO;
        } else if (compareTo(E) == 0) {
            return ONE;
        } else {
            // Verfahren noch unbekannt
            // Arithmetisch-geometrisches Mittel angestrebt.
            throw new UnsupportedOperationException("Not yet implemented");
        }
    }