Added LPSolve as a solver

1 files changed, 40 insertions, 0 deletions

diff --git a/Math/LinProg/Compile.hs b/Math/LinProg/Compile.hs
new file mode 100644
index 0000000..07398e7
--- /dev/null
+++ b/Math/LinProg/Compile.hs
@@ -0,0 +1,40 @@
+{-# LANGUAGE TemplateHaskell, FlexibleInstances, ScopedTypeVariables #-}
+
+module Math.LinProg.Compile (
+  compile
+  ,Equation
+  ,CompilerS(..)
+  ,objective
+  ,equals
+  ,leqs
+) where
+
+import Data.List
+import Math.LinProg.Types
+import Control.Lens
+import Control.Monad.State
+import Control.Monad.Free
+import Data.Maybe
+
+type Equation t v = (LinExpr t v, t) -- LHS and RHS
+
+data CompilerS t v = CompilerS {
+  _objective :: LinExpr t v
+  ,_equals :: [Equation t v]
+  ,_leqs :: [Equation t v]
+} deriving (Eq)
+
+$(makeLenses ''CompilerS)
+
+compile :: (Num t, Show t, Ord t, Eq v) => LinProg t v () -> CompilerS t v
+compile ast = compile' ast initCompilerS where
+  compile' (Free (Objective a c)) state = compile' c $ state & objective +~ a
+  compile' (Free (EqConstraint a b c)) state = compile' c $ state & equals %~ (split (a-b):)
+  compile' (Free (LeqConstraint a b c)) state = compile' c $ state & leqs %~ (split (a-b):)
+  compile' _ state = state
+
+  initCompilerS = CompilerS
+    0
+    []
+    []
+