XTCE13 — CNES CCSDS -- unit set "form" question

"A new attribute UnitFormType allows to specify a unit for calibrated values and another unit for uncalibrated values.

Why is this attribute defined with 3 enumerations? ‘raw’, ‘uncalibrated’ and ‘calibrated’?
"

Improve UnitFormTypes annotation

Improve the annotation on the UnitFormType to better explain the purpose of the enumerations.

Original type definition:

<simpleType name="UnitFormType">
<annotation>
<documentation>Optionally specify if this information pertains to something other than the calibrated/engineering value.</documentation>
</annotation>
<restriction base="string">
<enumeration value="calibrated"/>
<enumeration value="uncalibrated"/>
<enumeration value="raw"/>
</restriction>
</simpleType>

Updated type definition:

<simpleType name="UnitFormType">
<annotation>
<documentation xml:lang="en">Defines enumerated values to categorize a unit associated with a telemetered value. Typically the unit refers to the calibrated (engineering) value. In some cases the unit may be associated with the uncalibrated or raw values. Uncalibrated and raw here are typically synonymous, but there are exceptions.</documentation>
</annotation>
<restriction base="string">
<enumeration value="calibrated">
<annotation>
<documentation xml:lang="en">The unit of measure for this value refers to the engineer/calibrated value.</documentation>
</annotation>
</enumeration>
<enumeration value="uncalibrated">
<annotation>
<documentation xml:lang="en">The unit of measure for this value refers to the pre-calibrated data, after extraction from the data stream, when in the local native data type. This is unusual, but present in some cases.</documentation>
</annotation>
</enumeration>
<enumeration value="raw">
<annotation>
<documentation xml:lang="en">The unit of measure for this value refers to the raw binary value from the data stream, prior to conversion to the local native data type and application of calibrators.</documentation>
</annotation>
</enumeration>
</restriction>
</simpleType>