Inverse Words
Inverse words are associated with internal bit patterns containing
at least one inverse bit. An inverse bit is a bit whose 0 value is associated
with the presence of a word and whose value is 1 unless the word is present
in the label. Inverse words can have one or more bits associated with them.
The example below is for the simplest and most common case, where a single
0 bit is associated with a word. When a bit is used inversely, its value
in a NULL label must be 1. When such a word is combined with a label containing
no words, the resulting label does not contain the word.
Word2
| –0––––––
|
(NULL)
| –1––––––
|
(NULL)
| –1––––––
|
|
In the following example, two inverse words each associated with different
inverse (0) bits are combined. The resulting label contains neither of the
words.
Word2
| –0–––1––
|
Word6
| –1–––0––
|
(NULL)
| –1–––1––
|
|
In the example below, two labels containing the above inverse words
are combined. Only the inverse word that appears in both labels appears in
the resulting combination.
Word2
| –0–––1––
|
Word2 Word6
| –0–––0––
|
Word2
| –0–––1––
|
|