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Section 2

Definitions, Acronyms, and

Symbols

2.1

Conventions used in this document

Terms or letters set in Courier font represent literal strings that appear in FITS files.

In the case of keyword names, such as `NAXISn', the lower case letter represents a positive

integer index number, generally in the range 1 to 999. The emphasized words must,

shall, should, may, recommended, and optional in this document are to be interpreted

as described in IETF standard, RFC 2119 [16].

2.2

Defined Terms

u Used to designate an ASCII space character.

ANSI American National Standards Institute.

Array A sequence of data values. This sequence corresponds to the elements in a

rectilinear, n-dimension matrix (1 ≤ n ≤ 999, or n = 0 in the case of a null array).

Array value The value of an element of an array in a FITS file, without the application

of the associated linear transformation to derive the physical value.

ASCII American National Standard Code for Information Interchange.

ASCII character Any member of the 7-bit ASCII character set.

ASCII digit One of the 10 ASCII characters `0' through `9' which are represented by

decimal character codes 48 through 57 (hexadecimal 30 through 39).

ASCII NULL The ASCII character that has all 8 bits set to zero.

FITS Standard