implement mutateGenomeRemoveGene

1 files changed, 10 insertions, 2 deletions

diff --git a/src/Genome.hs b/src/Genome.hs
index 927005e..e0091b9 100644
--- a/src/Genome.hs
+++ b/src/Genome.hs
@@ -9,6 +9,7 @@ module Genome
   , mutateGenomeAddInternal
   , mutateGenomeRemoveInternal
   , mutateGenomeAddGene 
+  , mutateGenomeRemoveGene 
   ) where
 
 
@@ -149,8 +150,6 @@ mutateGenomeAddGene g r =
     gene = Gene so si w
   in (g {genes = gene:(genes g)}, r''')
 
-    
-
 randomSource :: RandomGen a => Genome -> a -> (NeuronIndex, a)
 randomSource g r =
   let
@@ -164,3 +163,12 @@ randomSink g r =
     (idx, r') = randomR (0, numInternal g + numOutput g - 1) r
     result = if idx < numInternal g then Internal idx else Output $ idx - numInput g
   in (result, r')
+
+
+-- remove a random gene
+mutateGenomeRemoveGene :: RandomGen a => Genome -> a -> (Genome, a)
+mutateGenomeRemoveGene g r =
+  let
+    (idx, r') = randomR (0, (length $ genes g) - 1) r
+    (front, _:back) = splitAt idx (genes g)
+  in (g {genes = front ++ back}, r')