CIFLIB Terminology

In order to ensure uniformity in the description and identification of variables and functions in the CIFLIB C language interface, an attempt has been made to use the following terminology in a consistent manner.

file

physical or persistent instance of a collection of data blocks in the I/O subsystem of an operating system.

path

the location of a file or directory in the I/O subsystem of an operating system.

data block

a named container for CIF definitions and declarations. A data block defines a unit of scope in a CIF dictionary of data file.

definition

a named collection of data item declarations encapsulated in a save_ block.

declaration

the instance of a CIF item.

dictionary

a CIF data block containing a collection of definitions.

item

the basic unit of CIF information composed of a keyword and value pair.

item name

the full identifier of CIF item which is the concatenation of the category name, a dot, and the keyword name.

keyword

the name of a CIF item within a CIF category.

value

the data associated with a CIF item.

category

a table of item values with a well defined basis. Key item values define the basis for the category and uniquely identify each tuple of item values in the category.

subcategory

a named collection of items within a CIF category.

category group

a named collection of CIF categories.

The following terminology has been used when referring to categories and category components:

row

a tuple of item values.

column

a list of item values.

row index

a zero based index identifying the row order.

column index

a zero based index identifying the column order.