Crystallographic Information Framework

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DDL dictionary version 2.1.3




     Codes defining conditions on the _item_type.code specification.

     'esd' permits a number string to contain an appended standard
       deviation number enclosed within parentheses, e.g. 4.37(5)

     'seq' permits data to be declared as a sequence of values
       separated by a comma <,> or a colon <:>.
       * The sequence v1,v2,v3,. signals that v1, v2, v3, etc.
         are alternative values or the data item.
       * The sequence v1:v2 signals that v1 and v2 are the boundary
         values of a continuous range of values. This mechanism
         was used to specify permitted ranges of an item in
         previous DDL versions.
      Combinations of alternate and range sequences are permitted.

Type: code

Mandatory item: yes

The data value must be one of the following:

no extra conditions apply to this data item

numbers may have esd values appended within parentheses

data may be declared as a comma- or colon-separated sequence

Category: item_type_conditions