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Item _array_data.data 
Description
The value of '_array_data.data' contains the array data
encapsulated in a STAR string.
The representation used is a variant on the
Multipurpose Internet Mail Extensions (MIME) specified
in RFC 2045-2049 by N. Freed et al. The boundary
delimiter used in writing an imgCIF or CBF is
"--CIF-BINARY-FORMAT-SECTION--" (including the
required initial "--").
The Content-Type may be any of the discrete types permitted
in RFC 2045; "application/octet-stream" is recommended.
If an octet stream was compressed, the compression should
be specified by the parameter 'conversions="x-CBF_PACKED"'
or the parameter 'conversions="x-CBF_CANONICAL"'.
The Content-Transfer-Encoding may be "BASE64",
"Quoted-Printable", "X-BASE8", "X-BASE10", or
"X-BASE16" for an imgCIF or "BINARY" for a CBF. The
octal, decimal and hexadecimal transfer encodings are
for convenience in debugging, and are not recommended
for archiving and data interchange.
In an imgCIF file, the encoded binary data begins after
the empty line terminating the header. In a CBF, the
raw binary data begins after an empty line terminating
the header and after the sequence:
Octet Hex Decimal Purpose
0 0C 12 (ctrl-L) Page break
1 1A 26 (ctrl-Z) Stop listings in MS-DOS
2 04 04 (Ctrl-D) Stop listings in UNIX
3 D5 213 Binary section begins
None of these octets are included in the calculation of
the message size, nor in the calculation of the
message digest.
The X-Binary-Size header specifies the size of the
equivalent binary data in octets. If compression was
used, this size is the size after compression, including
any book-keeping fields. An adjustment is made for
the deprecated binary formats in which 8 bytes of binary
header are used for the compression type. In that case,
the 8 bytes used for the compression type is subtracted
from the size, so that the same size will be reported
if the compression type is supplied in the MIME header.
Use of the MIME header is the recommended way to
supply the compression type. In general, no portion of
the binary header is included in the calculation of the size.
The X-Binary-Element-Type header specifies the type of
binary data in the octets, using the same descriptive
phrases as in '_array_structure.encoding_type'. The default
value is "unsigned 32-bit integer".
An MD5 message digest may, optionally, be used. The "RSA Data
Security, Inc. MD5 Message-Digest Algorithm" should be used.
No portion of the header is included in the calculation of the
message digest.
If the Transfer Encoding is "X-BASE8", "X-BASE10", or
"X-BASE16", the data is presented as octal, decimal or
hexadecimal data organized into lines or words. Each word
is created by composing octets of data in fixed groups of
2, 3, 4, 6 or 8 octets, either in the order ...4321 ("big-
endian") or 1234... (little-endian). If there are fewer
than the specified number of octets to fill the last word,
then the missing octets are presented as "==" for each
missing octet. Exactly two equal signs are used for each
missing octet even for octal and decimal encoding.
The format of lines is:
rnd xxxxxx xxxxxx xxxxxx
where r is "H", "O", or "D" for hexadecimal, octal or
decimal, n is the number of octets per word. and d is "<"
for ">" for the "...4321" and "1234..." octet orderings
respectively. The "==" padding for the last word should
be on the appropriate side to correspond to the missing
octets, e.g.
H4< FFFFFFFF FFFFFFFF 07FFFFFF ====0000
or
H3> FF0700 00====
For these hex, octal and decimal formats, only, comments
beginning with "#" are permitted to improve readability.
BASE64 encoding follows MIME conventions. Octets are
in groups of three, c1, c2, c3. The resulting 24 bits
are broken into four 6-bit quantities, starting with
the high-order six bits (c1 >> 2) of the first octet, then
the low-order two bits of the first octet followed by the
high-order 4 bits of the second octet ((c1 & 3)<<4 | (c2>>4)),
then the bottom 4 bits of the second octet followed by the
high order two bits of the last octet ((c2 & 15)<<2 | (c3>>6)),
then the bottom six bits of the last octet (c3 & 63). Each
of these four quantities is translated into an ASCII character
using the mapping:
1 2 3 4 5 6
0123456789012345678901234567890123456789012345678901234567890123
| | | | | | |
ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/
With short groups of octets padded on the right with one "="
if c3 is missing, and with "==" if both c2 and c3 are missing.
QUOTED-PRINTABLE encoding also follows MIME conventions, copying
octets without translation if their ASCII values are 32..38,
42, 48..57, 59..60, 62, 64..126 and the octet is not a ";"
in column 1. All other characters are translated to =nn, where
nn is the hexadecimal encoding of the octet. All lines are
"wrapped" with a terminating "=" (i.e. the MIME conventions
for an implicit line terminator are never used).
Category 
Mandatory Code 
Data Type Code