Other codes can be local ly defined at a given site , and these are described in Section A.2 . While the codes and their meanings are defined as part of this data format standard, we do not prescribe the form that the translation mechanism between these codes and their human-readable equivalents must take, although one current implementation based on using lookup tables is outlined in Appendix B . Process ing information is metadata which describes how the data were process ed. For example, if a day of our wind data was missing, we might decide to interpolat e in time to fill in that day's data. The process ing information would consist of a code indicating time interpolat ion and providing the starting and ending days of the interpolat ion.
Auxiliary information is information which refers to or supplements the data.
While process ing information should be thought of as labels or tags applied to sections of the data, the auxiliary information on the other hand is more in the nature of a group of secondary variables which could not stand on their own as data in their own right, but which by their nature refer to the actual data. Data can be both pack ed and compress ed. We could then use a compress ion routine to compress this pack ed data into a byte array whose length is determined by the bit patterns in the data. To read the data, we would first uncompress it and then unpack it using the metadata provided in the specification of the winds. The collection of the data, the specification of its dimension s, and its metadata are collectively referred to as a data object .