add mut_genome_contract

1 files changed, 19 insertions, 0 deletions

diff --git a/src/genome/genome.js b/src/genome/genome.js
index 16b5e4d..d2650b5 100644
--- a/src/genome/genome.js
+++ b/src/genome/genome.js
@@ -106,6 +106,25 @@ export function mut_genome_expand(
 }

 

 

+export function mut_genome_contract(

+  [n_input, n_internal, n_output, genome], r

+) {

+  const contract_idx = Math.floor(n_internal * r) + n_input;

+  const new_source = (source) => source >= contract_idx ? source-1 : source;

+  const new_sink   = (sink)   => sink > contract_idx ? sink-1 : sink;

+

+  const new_genome = genome.map(([source, sink, weight]) => [

+    new_source(source), 

+    new_sink(sink), 

+    weight,

+  ]);

+

+  return [

+    n_input, n_internal-1, n_output, new_genome

+  ];

+}

+

+

 export function mut_genome_insert(

   [n_input, n_internal, n_output, genome], 

   weight_max,