@type model_option() ::
  {:store_log, [log_entry_type()]}
  | {:shift_probabilities, boolean()}
  | {:sanitize_tokens, boolean()}
  | {:order, integer()}

Model options that could be set during creation in a call to load/3 or with configure/2:

• store_log: determines what data to put in the operation log, all of them by default:
  • :start - model is loaded
  • :end - model is unloaded
  • :train: training requests
  • :gen: generation results
• shift_probabilities: gives less popular generation paths more chance to get used, which makes the output more original but may produce nonsense; false by default
• sanitize_tokens: ignores letter case and punctuation when switching states, but still keeps the output as-is; false by default, can't be changed once the model is created
• order: order of the chain, i.e. how many previous tokens the next one is based on; 2 by default, can never be changed once the model is created

@type tag_query() :: %{required(term()) => non_neg_integer()}

If data was tagged when training, you can use tag queries to alter the probabilities of certain generation paths

examples

Examples:

# training
iex> Markov.train(model, "hello earth", [
  {:action, :saying_hello}, # <- terms of any type can function as tags
  {:subject_type, :planet},
  {:subject, "earth"},
  :lowercase
])
:ok
iex> Markov.train(model, "Hello Elixir", [
  {:action, :saying_hello},
  {:subject_type, :programming_language},
  {:subject, "Elixir"},
  :uppercase
])
:ok


# simple generation - both paths have equal probabilities
iex> Markov.generate_text(model)
{:ok, "hello earth"}
iex> Markov.generate_text(model)
{:ok, "hello Elixir"}

# All generation paths have a score of 1 by default. Here we're telling
# Markov to add 1 point to paths tagged with `:uppercase`;
# "hello Elixir" now has a score of 2 and "hello earth" has a score of 1.
# Thus, "hello Elixir" has a probability of 2/3, and "hello earth" has
# that of 1/3
iex> Markov.generate_text(model, %{uppercase: 1})
{:ok, "hello Elixir"}
iex> Markov.generate_text(model, %{uppercase: 1})
{:ok, "hello Elixir"}
iex> Markov.generate_text(model, %{uppercase: 1})
{:ok, "hello earth"}