def test_wet_psychrometric_vapor_pressure(): """Test calculation of vapor pressure from wet and dry bulb temperatures.""" p = 1013.25 * units.mbar dry_bulb_temperature = 20. * units.degC wet_bulb_temperature = 18. * units.degC psychrometric_vapor_pressure = psychrometric_vapor_pressure_wet(dry_bulb_temperature, wet_bulb_temperature, p) assert_almost_equal(psychrometric_vapor_pressure, 19.3673 * units.mbar, 3)