anchor.diff:  %% --------------------------------------------------------------------- %%
   %% @doc Creates an artificial neural network with any number of layers. 
   %% The Layers tuple size describe the number of layers while each position
  -%% sets the size of the layer. See the FANN documentation of create_standard:
  +%% sets the size of the layer. 
  +%%
  +%% In the options map you can specify which type of network you want to create.
  +%% Set Options to `#{type=>sparse, conn_rate => 0.1}' to create a sparse type
  +%% of ANN with the given connection rate. It is important to specify the 
  +%% connection rate here as it will not be configurable later. 
  +%%
  +%% In the same way you can create a shortcut type of ANN by setting
  +%% Options to `#{type=shortcut}'. 
  +%%
  +%% Other options you can set are the same as those possible to set by 
  +%% set_params/2.
  +%%
  +%%See the FANN documentation of create_standard:
   %% [http://libfann.github.io/fann/docs/files/fann-h.html#fann_create_standard]
   %% @end
   %% --------------------------------------------------------------------- %%
  --spec create_on(Instance::pid(), Layers::tuple(), Options::options()) ->
  +-spec create_on(Instance::pid(), Layers::tuple(), Options::create_options()) ->
   		       network_ref().
   create_on(Instance, Layers, Options) 
     when Instance == ?MODULE; is_pid(Instance),
  
positive.code: %% @equiv get_params_on({@module}, Network)
  %% @end
  %% --------------------------------------------------------------------- %%
  -spec get_params(Network::network_ref()) -> map().
  get_params(Network) 
    when is_reference(Network) ->
      get_params_on(?MODULE, Network).
  
negative.code: 		 train_error_function |
  		 train_stop_function |
  		 training_algorithm.
  
  -type set_params() :: #{param() => term()}.
  
  -type create_options() :: #{type => standard | sparse | shortcut,
  			    conn_rate => number(),
  			    param() => term()
  			 }.
  
  -type connections()    :: #{{FromNeuron::integer(),
  			     ToNeuron::integer()} => Weight::number()}.
  