{
  "cases": [
    {
      "id": "two-international-feet",
      "inputs": {
        "value": "2",
        "from_unit_id": "cx:ft_i",
        "to_unit_id": "cx:m",
        "quantity_kind": "length",
        "role": "scalar",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "exact": {
          "numerator": "381",
          "denominator": "625",
          "pi_power": 0
        },
        "decimal": "6.096e-1",
        "binary64_hex": "3fe381d7dbf487fd",
        "binary64_status": "finite"
      },
      "source": "https://www.nist.gov/pml/us-surveyfoot/revised-unit-conversion-factors",
      "derivation": "2 × 0.3048 m = 0.6096 m."
    },
    {
      "id": "length-reverse",
      "inputs": {
        "value": "381",
        "from_unit_id": "cx:m",
        "to_unit_id": "cx:ft_i",
        "quantity_kind": "length",
        "role": "scalar",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "exact": {
          "numerator": "1250",
          "denominator": "1",
          "pi_power": 0
        },
        "decimal": "1.25e3",
        "binary64_hex": "4093880000000000",
        "binary64_status": "finite"
      },
      "source": "https://www.nist.gov/pml/us-surveyfoot/revised-unit-conversion-factors",
      "derivation": "381 ÷ (381/1250) = 1250."
    },
    {
      "id": "celsius-point",
      "inputs": {
        "value": "0",
        "from_unit_id": "cx:degC",
        "to_unit_id": "cx:K",
        "quantity_kind": "temperature",
        "role": "point",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "exact": {
          "numerator": "5463",
          "denominator": "20",
          "pi_power": 0
        },
        "decimal": "2.7315e2",
        "binary64_hex": "4071126666666666",
        "binary64_status": "finite"
      },
      "source": "https://www.nist.gov/pml/special-publication-330/sp-330-section-2",
      "derivation": "T/K = 0 + 273.15."
    },
    {
      "id": "fahrenheit-interval",
      "inputs": {
        "value": "18",
        "from_unit_id": "cx:degF",
        "to_unit_id": "cx:degC",
        "quantity_kind": "temperature",
        "role": "interval",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "exact": {
          "numerator": "10",
          "denominator": "1",
          "pi_power": 0
        },
        "decimal": "1e1",
        "binary64_hex": "4024000000000000",
        "binary64_status": "finite"
      },
      "source": "https://www.nist.gov/pml/special-publication-811/nist-guide-si-appendix-b-conversion-factors/nist-guide-si-appendix-b8",
      "derivation": "An interval scales by 5/9. 18 × 5/9 = 10."
    },
    {
      "id": "absolute-zero",
      "inputs": {
        "value": "-273.15",
        "from_unit_id": "cx:degC",
        "to_unit_id": "cx:K",
        "quantity_kind": "temperature",
        "role": "point",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "exact": {
          "numerator": "0",
          "denominator": "1",
          "pi_power": 0
        },
        "decimal": "0",
        "binary64_hex": "0000000000000000",
        "binary64_status": "finite"
      },
      "source": "https://www.nist.gov/pml/special-publication-330/sp-330-section-2",
      "derivation": "−273.15 + 273.15 = 0 K."
    },
    {
      "id": "below-absolute-zero",
      "inputs": {
        "value": "-273.1500000000000001",
        "from_unit_id": "cx:degC",
        "to_unit_id": "cx:K",
        "quantity_kind": "temperature",
        "role": "point",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "error": {
          "code": "VALUE_OUT_OF_RANGE",
          "field": "value"
        }
      },
      "source": "https://www.calculatorx.com/developers/units",
      "derivation": "Exact input plus 273.15 K gives a negative temperature point."
    },
    {
      "id": "half-turn",
      "inputs": {
        "value": "180",
        "from_unit_id": "cx:deg",
        "to_unit_id": "cx:rad",
        "quantity_kind": "plane_angle",
        "role": "scalar",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "exact": {
          "numerator": "1",
          "denominator": "1",
          "pi_power": 1
        },
        "decimal": "3.141592653589793238462643383279503e0",
        "binary64_hex": "400921fb54442d18",
        "binary64_status": "finite"
      },
      "source": "https://www.nist.gov/pml/special-publication-330/sp-330-section-5",
      "derivation": "180 × π/180 = π rad. The decimal follows the pinned 34-digit policy."
    },
    {
      "id": "angle-pi-cancels",
      "inputs": {
        "value": "90",
        "from_unit_id": "cx:deg",
        "to_unit_id": "cx:deg",
        "quantity_kind": "plane_angle",
        "role": "scalar",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "exact": {
          "numerator": "90",
          "denominator": "1",
          "pi_power": 0
        },
        "decimal": "9e1",
        "binary64_hex": "4056800000000000",
        "binary64_status": "finite"
      },
      "source": "https://www.nist.gov/pml/special-publication-330/sp-330-section-5",
      "derivation": "The symbolic scale π/180 cancels in an identity conversion."
    },
    {
      "id": "cross-kind",
      "inputs": {
        "value": "1",
        "from_unit_id": "cx:m",
        "to_unit_id": "cx:Hz",
        "quantity_kind": "length",
        "role": "scalar",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "error": {
          "code": "QUANTITY_KIND_MISMATCH",
          "field": "quantity_kind"
        }
      },
      "source": "https://www.calculatorx.com/developers/units",
      "derivation": "Hertz does not support the length quantity kind."
    },
    {
      "id": "scalar-temperature",
      "inputs": {
        "value": "1",
        "from_unit_id": "cx:degC",
        "to_unit_id": "cx:K",
        "quantity_kind": "temperature",
        "role": "scalar",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "error": {
          "code": "UNIT_ROLE_MISMATCH",
          "field": "role"
        }
      },
      "source": "https://www.calculatorx.com/developers/units",
      "derivation": "The temperature conversion requires a point or interval role."
    },
    {
      "id": "unavailable-snapshot",
      "inputs": {
        "value": "1",
        "from_unit_id": "cx:m",
        "to_unit_id": "cx:ft_i",
        "quantity_kind": "length",
        "role": "scalar",
        "snapshot": "unavailable"
      },
      "expected": {
        "error": {
          "code": "SNAPSHOT_MISMATCH",
          "field": "snapshot"
        }
      },
      "source": "https://www.calculatorx.com/developers/units",
      "derivation": "The requested snapshot is outside the pinned contract."
    },
    {
      "id": "decimal-even-midpoint",
      "inputs": {
        "value": "1.2345678901234567890123456789012345",
        "from_unit_id": "cx:m",
        "to_unit_id": "cx:m",
        "quantity_kind": "length",
        "role": "scalar",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "exact": {
          "numerator": "2469135780246913578024691357802469",
          "denominator": "2000000000000000000000000000000000",
          "pi_power": 0
        },
        "decimal": "1.234567890123456789012345678901234e0",
        "binary64_hex": "3ff3c0ca428c59fb",
        "binary64_status": "finite"
      },
      "source": "https://www.calculatorx.com/developers/units",
      "derivation": "The 35th digit is exactly 5. Retain the even 34th digit."
    },
    {
      "id": "binary64-overflow",
      "inputs": {
        "value": "1e308",
        "from_unit_id": "cx:km",
        "to_unit_id": "cx:m",
        "quantity_kind": "length",
        "role": "scalar",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "exact": {
          "numerator": "100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
          "denominator": "1",
          "pi_power": 0
        },
        "decimal": "1e311",
        "binary64_hex": null,
        "binary64_status": "overflow"
      },
      "source": "https://www.calculatorx.com/developers/units",
      "derivation": "1e308 × 1000 = 1e311, beyond finite binary64."
    },
    {
      "id": "binary64-underflow",
      "inputs": {
        "value": "0.000000000000000001e-308",
        "from_unit_id": "cx:m",
        "to_unit_id": "cx:km",
        "quantity_kind": "length",
        "role": "scalar",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "exact": {
          "numerator": "1",
          "denominator": "100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
          "pi_power": 0
        },
        "decimal": "1e-329",
        "binary64_hex": null,
        "binary64_status": "underflow"
      },
      "source": "https://www.calculatorx.com/developers/units",
      "derivation": "1e−326 ÷ 1000 = 1e−329, below half the least positive binary64 subnormal."
    },
    {
      "id": "survey-foot-exact",
      "inputs": {
        "value": "3937",
        "from_unit_id": "cx:ft_us",
        "to_unit_id": "cx:m",
        "quantity_kind": "length",
        "role": "scalar",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "exact": {
          "numerator": "1200",
          "denominator": "1",
          "pi_power": 0
        },
        "decimal": "1.2e3",
        "binary64_hex": "4092c00000000000",
        "binary64_status": "finite"
      },
      "source": "https://www.nist.gov/pml/us-surveyfoot/revised-unit-conversion-factors",
      "derivation": "3937 survey feet times exactly 1200/3937 m per foot equals 1200 m."
    },
    {
      "id": "international-to-survey",
      "inputs": {
        "value": "1500000",
        "from_unit_id": "cx:ft_i",
        "to_unit_id": "cx:ft_us",
        "quantity_kind": "length",
        "role": "scalar",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "exact": {
          "numerator": "1499997",
          "denominator": "1",
          "pi_power": 0
        },
        "decimal": "1.499997e6",
        "binary64_hex": "4136e35d00000000",
        "binary64_status": "finite"
      },
      "source": "https://www.nist.gov/pml/us-surveyfoot/revised-unit-conversion-factors",
      "derivation": "Multiply by (381/1250)/(1200/3937) = 499999/500000."
    },
    {
      "id": "kelvin-point-reverse",
      "inputs": {
        "value": "298.15",
        "from_unit_id": "cx:K",
        "to_unit_id": "cx:degC",
        "quantity_kind": "temperature",
        "role": "point",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "exact": {
          "numerator": "25",
          "denominator": "1",
          "pi_power": 0
        },
        "decimal": "2.5e1",
        "binary64_hex": "4039000000000000",
        "binary64_status": "finite"
      },
      "source": "https://www.nist.gov/pml/special-publication-330/sp-330-section-2",
      "derivation": "Subtract the exact offset 273.15 from 298.15 K."
    },
    {
      "id": "kelvin-interval-reverse",
      "inputs": {
        "value": "-7.25",
        "from_unit_id": "cx:K",
        "to_unit_id": "cx:degC",
        "quantity_kind": "temperature",
        "role": "interval",
        "snapshot": "0.3.0-preview.3"
      },
      "expected": {
        "exact": {
          "numerator": "-29",
          "denominator": "4",
          "pi_power": 0
        },
        "decimal": "-7.25e0",
        "binary64_hex": "c01d000000000000",
        "binary64_status": "finite"
      },
      "source": "https://www.nist.gov/pml/special-publication-330/sp-330-section-2",
      "derivation": "Temperature intervals have identical kelvin and Celsius scale and no offset."
    }
  ]
}