diff --git a/PSB2_path.txt b/PSB2_path.txt
index b449bfb..c9a901d 100644
--- a/PSB2_path.txt
+++ b/PSB2_path.txt
@@ -1 +1 @@
-/Volumes/Samsung_T5/Evolutionary Computing/PSB2/datasets
\ No newline at end of file
+/Volumes/Samsung_T5/EvolutionaryComputing/PSB2
\ No newline at end of file
diff --git a/src/propeller/core.cljc b/src/propeller/core.cljc
index bced168..830635f 100755
--- a/src/propeller/core.cljc
+++ b/src/propeller/core.cljc
@@ -7,11 +7,11 @@
 
 (defn eval-problem-var
   [problem-name var-name]
-  (eval (symbol (str "propeller.problems." problem-name "/" var-name)))
+  (eval (symbol (str "propeller.problems." problem-name "/" var-name))))
   ;; Overload 2: PSB specific
   ;; Passes into eval
-  [problem-name var-name PSB2-name]
-  ((eval (symbol (str "propeller.problems." problem-name "/" var-name))) PSB2-name))
+  ; [problem-name var-name psb2-name]
+  ; ((eval (symbol (str "propeller.problems." problem-name "/" var-name))) psb2-name))
 
 (defn -main
   "Runs propel-gp, giving it a map of arguments."
@@ -29,13 +29,14 @@
     (println (str "Set path to PSB2 as " (second args)))
     (System/exit 1))
 
+  ;; ** worked on GENERAL SOLUTION, save for later **
   ;; Creates PSB2 problems
-  (when (= (first args) "PSB2")
+  ;(when (= (first args) "PSB2")
     ;; For tomorrow, Figure out what this does?
-    (require (symbol (str "propeller.problems.PSB2" (first args))))
+    ;(require (symbol (str "propeller.problems.PSB2" (first args)))))
     ;; For tomorrow, add the gp/gp function here
     ;; ---
-    
+  ;; ** end save for later **
 
   ;; Creates regular problems
   (require (symbol (str "propeller.problems." (first args))))
diff --git a/src/propeller/gp.cljc b/src/propeller/gp.cljc
index 0eb0426..ad2a4a9 100755
--- a/src/propeller/gp.cljc
+++ b/src/propeller/gp.cljc
@@ -61,7 +61,7 @@
             (if (zero? (:total-error (error-function argmap best-individual :test)))
               (println "Test cases passed.")
               (println "Test cases failed."))
-            ;(#?(:clj shutdown-agents))
+            ; (#?(:clj shutdown-agents))
             )
         ;;
         (>= generation max-generations)
diff --git a/src/propeller/problems/PSB2_Problems.cljc b/src/propeller/problems/PSB2_Problems.cljc
index fea00c9..569238c 100644
--- a/src/propeller/problems/PSB2_Problems.cljc
+++ b/src/propeller/problems/PSB2_Problems.cljc
@@ -1,15 +1,78 @@
 (ns propeller.problems.PSB2-Problems
-  (:require [psb2.core :as psb2]))
+  (:require [psb2.core :as psb2]
+            [propeller.genome :as genome]
+            [propeller.push.interpreter :as interpreter]
+            [propeller.utils :as utils]
+            [propeller.push.utils.helpers :refer [get-stack-instructions]]
+            [propeller.push.state :as state]
+            [propeller.tools.math :as math]))
 
 ;; Get path from text file
 (def PSB2-path (slurp "PSB2_path.txt"))
 
-(defn train-and-test
-  "Returns the train and test sets from PSB2 using Prof. Helmuth's function"
-  ;; Default to 200 train and 2000 test
-  [problem]
-  (psb2/fetch-examples PSB2-path problem 200 2000)
-  ;; To with 2 extra args, can customise train and test set sizes
-  [problem train test]
-  (psb2/fetch-examples PSB2-path problem train test))
+;; ** worked on GENERAL SOLUTION for PSB2, save for later **
+;(defn train-and-test
+;  "Returns the train and test sets from PSB2 using Prof. Helmuth's function"
+;  ;; Default to 200 train and 2000 test
+;  [problem]
+;  (psb2/fetch-examples PSB2-path problem 200 2000)
+;  ;; To with 2 extra args, can customise train and test set sizes
+;  [problem train test]
+;  (psb2/fetch-examples PSB2-path problem train test))
+;; ** end save for later **
+
+;; train and test set generation: Specific function for fuel-cost,
+;; single PSB2 problem implementation
+;(defn train-and-test-data
+;  "Returns the train and test sets "
+;  []
+;  (psb2/fetch-examples PSB2-path "fuel-cost" 200 2000))
+
+(def train-and-test-data (psb2/fetch-examples PSB2-path "fuel-cost" 200 2000))
+
+
+
+;; Instruction set: ported from number-io, meant for fuel-cost
+(def instructions
+  (utils/not-lazy
+    (concat
+      ;; stack-specific instructions
+      (get-stack-instructions #{:float :integer :print})
+      ;; input instructions
+      (list :in1))))
+      ;; ERCs (constants)
+      ;; (list random-float random-int))))
+
+;; Error function from number-io
+(defn error-function
+  ([argmap individual]
+   (error-function argmap individual :train))
+  ([argmap individual subset]
+   (let [program (genome/plushy->push (:plushy individual) argmap)
+         data (get train-and-test-data subset)
+         inputs (map (fn [i] (get i :input1)) (get train-and-test-data subset))
+         correct-outputs (map (fn [i] (get i :output1)) (get train-and-test-data subset))
+         outputs (map (fn [input]
+                        (state/peek-stack
+                          (interpreter/interpret-program
+                            program
+                            (assoc state/empty-state :input {:in1 (first input)}
+                                                     :output '(""))
+                            (:step-limit argmap))
+                          :output))
+                      inputs)
+         parsed-outputs (map (fn [output]
+                               (try (read-string output)
+                                    #?(:clj (catch Exception e 1000.0)
+                                       :cljs (catch js/Error. e 1000.0))))
+                             outputs)
+         errors (map (fn [correct-output output]
+                       (min 1000.0 (math/abs (- correct-output output))))
+                     correct-outputs
+                     parsed-outputs)]
+     (assoc individual
+       :behaviors parsed-outputs
+       :errors errors
+       :total-error #?(:clj (apply +' errors)
+                       :cljs (apply + errors))))))
 
diff --git a/src/propeller/problems/simple_regression.cljc b/src/propeller/problems/simple_regression.cljc
index 94508cf..5d19460 100755
--- a/src/propeller/problems/simple_regression.cljc
+++ b/src/propeller/problems/simple_regression.cljc
@@ -71,9 +71,4 @@
        :behaviors outputs
        :errors errors
        :total-error #?(:clj  (apply +' errors)
-                       :cljs (apply + errors))))))
-
-
-(defn test-thingy
-  [x]
-  (println x))
+                       :cljs (apply + errors))))))
\ No newline at end of file