Method unit

ThirdParty/libproj/vtklibproj/src/grids.cpp:2515–2517

    int samplesPerPixel() const override { return m_grid->samplesPerPixel(); }

    std::string unit(int sample) const override {
        return m_grid->metadataItem("UNITTYPE", sample);
    }

    std::string description(int sample) const override {
        return m_grid->metadataItem("DESCRIPTION", sample);