Method map

src/backend/worksheet/plots/cartesian/CartesianScale.cpp:84–90

	~LogScale() override = default;

	bool map(double* value) const override {
		CHECK(*value > 0)

		*value = log(*value) / log(m_c) * m_b + m_a;

		return true;
	}

	bool inverseMap(double* value) const override {
		*value = pow(m_c, (*value - m_a) / m_b);