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markov2seq​

markov2seq(
    @matrix ## llll (required)
    @maxlength 25
    @start null
    @autoclear 1
    @useseed 0
    @prepad '^'
    @postpad '$'
) -> llll

Generates a sequence using a given Markov transition matrix. If a starting state is specified, the function attempts to find transitions from it. Otherwise, it selects a random state from the transition matrix. The function supports both 0th-order Markov chains (where each state is chosen independently with a probability distribution) and higher-order Markov chains (where state transitions depend on previous elements). If the sequence reaches the maximum length or no valid transitions are available, generation stops. See seq2markov.

Arguments​

  • @matrix [llll]: Transition probability matrix. (required)
  • @maxlength [int]: Maximum length of the generated sequence. (default: 25).
  • @start [int]: Initial state for the sequence. If null, a random state is chosen. (default: null).
  • @autoclear [int]: Allow sequence to automatically reset when no valid transitions exist. (default: 1).
    • 0: Off
    • 1: On
  • @useseed [int]: Use seeded random function for persistent output (default: 0).
    • 0: Off
    • 1: On
  • @prepad [symbol]: Padding symbol representing beginning of the sequence. (default: '^').
  • @postpad [symbol]: Padding symbol representing end of a sequence. (default: '$').

Output​

Generated sequence of elements based on the given Markov transition matrix [llll]

Usage​

$events = importmidi('bach.mid'); ## import MIDI file
## get pitch from each event
$pitches = for $e in $events collect $e.getkey('pitch');
## build 2nd-order Markov model from pitch sequence
$matrix = seq2markov(@sequence $pitches @order 2);
## generate pitch sequence of size 50 from Markov model
$pitchseq = markov2seq(@matrix $matrix @maxlength 50);
$t = 0;
## Transcribe pitches
for $pitch in $pitchseq do (
    ezsampler(@pitch $pitch).transcribe($t);
    $t += 120
);
render(@play 1)