All compile errors fixed, but now there's a weird NaN. The wonders never cease

app/Main.hs

@@ -1,15 +1,20 @@
 module Main where
 
 import Control.Lens
-import Criterion.Main
+import Control.Lens.Unsound (adjoin)
+import Control.Monad.Writer
+-- import Criterion.Main
+import Data.Default
 import Data.Either
 import Petzval.Optics
 import Petzval.Optics.RTM
 import Petzval.System
+import Petzval.Merit
 import Petzval.Trace
 import Petzval.Calculations
 import Petzval.Optimization
 import Petzval.Types
+import System.Environment (getArgs)
 import Linear
 import Numeric.AD.Mode (Scalar, Mode)
 import qualified Numeric.LinearAlgebra as L
@@ -41,13 +46,13 @@ system2 =
   , Surface{_material=s_sk16, _outsideRadius = 11, _roc=656.66349, _thickness = 4.5}
   , Surface{_material = air, _outsideRadius = 11, _roc = -33.50754, _thickness = 86.48643}
   ]
-  where s_sk16 = ConstMat 1.620408
-        s_f4 = ConstMat 1.616589
+  where s_sk16 = constMat 1.620408 :: SellemeierMat
+        s_f4 = constMat 1.616589
 
 merit :: (Material mat, Calcuable a) => [Element mat a] -> a
 -- merit :: (Material mat) => [Element mat Double] -> Double
 merit system = result 
-  where baked = bake 0.587618 system
+  where baked = bake 0.5875618 system
         ep = entrancePupil baked
         result = sum
           . map (^2)
@@ -63,6 +68,17 @@ merit system = result
 type Id a = a -> a
 
 
+doOptimize steps = runWriterT $ optimizeDLS cfg vars merit system1
+    where merit = mkMerit [ DynMerit $ TW 50 100 $ BFL Nothing
+                          , DynMerit $ TW 0 1 $ SpotSize Nothing
+                          ]
+          vars :: VariableSet
+          vars = (ix 1 . roc) `adjoin` (ix 2 . roc)
+          vars2 = undefined -- foldl1 adjoin
+                  -- [ ix 1.roc , ix 2.roc]
+          cfg = def{maxSteps = steps}
+
+              
 
 main :: IO ()
 main =
@@ -70,10 +86,14 @@ main =
       ep = (entrancePupil baked){position=20.4747094540}
       fa = 20
   in do
+    [arg] <- getArgs
+    let steps = read arg
     print $ L.norm_2  (L.fromList [3.0 , 4.0] :: L.Vector Double)
+    doOptimize steps >>= print
     putStrLn $ show ep
     putStrLn $ show $ rearFocalLength $ lensRTM baked
     putStrLn $ show $ mconcat (seidel ep fa baked :: [Seidel Double])
+    
  {-   defaultMain [
       bgroup "merit" [ bench "system1" $ nf merit (system1 :: [Element SellemeierMat Double])
                      , bench "system2" $ nf merit (system2 :: [Element ConstMat Double])