There are a number of non-obvious rules for choosing data names, which we should document. The ones that spring to mind are:
- A data name should be formed as
_<category>.<object>.
- Characters in data names are restricted to alphanumeric symbols,
_ and .
- An
object data name section = special_details is usually used to record information not captured in other tags of the category
_su should be appended to object to represent the SU of Measurand data names- Where category
B is a child category of category A, all <object> values of B should be distinct from any <object> values in A, with the exception of linked key data names. This is because dREL may refer to items in B as if they are part of A using only their object_id.
- Where
Loop category B is a child category of Loop category A, the category name for B would normally be prefixed with the category name for A, followed by an underscore. For example, atom_type_scat is a child category of atom_type.
- Where a category provides overall information for looped items in a separate category, conventionally
s is appended to the looped categories name, for example, reflns provides summary information for reflections in the refln loop.
- When creating DDLm data names to match legacy DDL1 data names, minimal changes to the ideal
_<category>.<object> form should be made
- Not all data names conform to these rules due to the need to consider legacy naming from DDL1 dictionaries.
If these sound like a good start, we should create a document.
There are a number of non-obvious rules for choosing data names, which we should document. The ones that spring to mind are:
_<category>.<object>._and.objectdata name section =special_detailsis usually used to record information not captured in other tags of the category_sushould be appended toobjectto represent the SU ofMeasuranddata namesBis a child category of categoryA, all<object>values ofBshould be distinct from any<object>values inA, with the exception of linked key data names. This is because dREL may refer to items inBas if they are part ofAusing only theirobject_id.LoopcategoryBis a child category ofLoopcategoryA, the category name forBwould normally be prefixed with the category name forA, followed by an underscore. For example,atom_type_scatis a child category ofatom_type.sis appended to the looped categories name, for example,reflnsprovides summary information for reflections in thereflnloop._<category>.<object>form should be madeIf these sound like a good start, we should create a document.