in range [0, 32767] may be attached to each rule. They are used when several
rules are candidates in "RND", "LIN", "SUB" or "SUB1" grammars. A rule with
weight <0> is inactive
The weight value is indicated between angle brackets, e.g. <43>.
Default weight is <127>. It is convenient to use weights in range 0..127
so that they may be set by MIDI controllers, using parameters K1, K2... (see
any rule may gain a positive or negative weight increment each time it is
applied. For instance, a rule with weight <100-30> will have successive
weights 100, 70, 40, 10 and 0, and therefore cannot be applied more than four
times in the same production.
good idea for checking a grammar is to set the weights of some rules to
<1-1> (or <n-n> for any integer
These rules can be used only one time. Once an item has been produced,
produce a new one without resetting rule weights (the option is available by
typing cmd-option space): the next item will be based on different rules since
former ones have become inactive.
using a subgrammar with dynamically decrementing weights, derivations of the
work string stop when all candidate rules have weight <0>. This is a
common way of avoiding endless derivations.
weights dynamically on context-sensitive rules is a simple way to let patterns
"emerge" randomly: some rules are becoming more active while they "inhibit"
is necessary when a rule should absolutely be applied as soon as it becomes a
candidate. (BP2 actually selects the
candidate rule with an
An infinite weight is notated "<∞>". On US keyboards, character
'∞' is obtained by typing '5' with the 'option' key down.