Update middle-character for new problem specification scheme

src/propeller/problems/PSB2/middle_character.cljc

@@ -17,6 +17,8 @@
 ; Source: https://arxiv.org/pdf/2106.06086.pdf
 ; ===============================================================
 
+(def train-and-test-data (psb2/fetch-examples "data" "middle-character" 200 2000))
+
 (defn random-int [] (- (rand-int 201) 100))
 
 (def instructions
@@ -32,11 +34,8 @@
       (list "" 0 1 2 random-int))))
 
 (defn error-function
-  ([argmap individual]
-   (error-function argmap individual :train))
-  ([argmap individual subset]
+  [argmap data individual]
   (let [program (genome/plushy->push (:plushy individual) argmap)
-         data (get (get argmap :train-and-test-data) subset)
         inputs (map (fn [i] (get i :input1)) data)
         correct-outputs (map (fn [i] (get i :output1)) data)
         outputs (map (fn [input]
@@ -62,6 +61,10 @@
       :behaviors parsed-outputs
       :errors errors
       :total-error #?(:clj  (apply +' errors)
-                       :cljs (apply + errors))))))
-
+                      :cljs (apply + errors)))))
 
+(def arglist
+  {:instructions   instructions
+   :error-function error-function
+   :training-data  (:train train-and-test-data)
+   :testing-data   (:test train-and-test-data)})