src/HOL/Matrix/cplex/Cplex_tools.ML
changeset 37766 a779f463bae4
parent 37763 38456e144423
parent 37765 26bdfb7b680b
child 37767 a2b7a20d6ea3
--- a/src/HOL/Matrix/cplex/Cplex_tools.ML	Sat Jul 10 22:39:16 2010 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,1225 +0,0 @@
-(*  Title:      HOL/Matrix/cplex/Cplex_tools.ML
-    Author:     Steven Obua
-*)
-
-signature CPLEX =
-sig
-
-    datatype cplexTerm = cplexVar of string | cplexNum of string | cplexInf
-                       | cplexNeg of cplexTerm
-                       | cplexProd of cplexTerm * cplexTerm
-                       | cplexSum of (cplexTerm list)
-
-    datatype cplexComp = cplexLe | cplexLeq | cplexEq | cplexGe | cplexGeq
-
-    datatype cplexGoal = cplexMinimize of cplexTerm
-               | cplexMaximize of cplexTerm
-
-    datatype cplexConstr = cplexConstr of cplexComp *
-                      (cplexTerm * cplexTerm)
-
-    datatype cplexBounds = cplexBounds of cplexTerm * cplexComp * cplexTerm
-                      * cplexComp * cplexTerm
-             | cplexBound of cplexTerm * cplexComp * cplexTerm
-
-    datatype cplexProg = cplexProg of string
-                      * cplexGoal
-                      * ((string option * cplexConstr)
-                         list)
-                      * cplexBounds list
-
-    datatype cplexResult = Unbounded
-             | Infeasible
-             | Undefined
-             | Optimal of string *
-                      (((* name *) string *
-                    (* value *) string) list)
-
-    datatype cplexSolver = SOLVER_DEFAULT | SOLVER_CPLEX | SOLVER_GLPK
-
-    exception Load_cplexFile of string
-    exception Load_cplexResult of string
-    exception Save_cplexFile of string
-    exception Execute of string
-
-    val load_cplexFile : string -> cplexProg
-
-    val save_cplexFile : string -> cplexProg -> unit
-
-    val elim_nonfree_bounds : cplexProg -> cplexProg
-
-    val relax_strict_ineqs : cplexProg -> cplexProg
-
-    val is_normed_cplexProg : cplexProg -> bool
-
-    val get_solver : unit -> cplexSolver
-    val set_solver : cplexSolver -> unit
-    val solve : cplexProg -> cplexResult
-end;
-
-structure Cplex  : CPLEX =
-struct
-
-datatype cplexSolver = SOLVER_DEFAULT | SOLVER_CPLEX | SOLVER_GLPK
-
-val cplexsolver = Unsynchronized.ref SOLVER_DEFAULT;
-fun get_solver () = !cplexsolver;
-fun set_solver s = (cplexsolver := s);
-
-exception Load_cplexFile of string;
-exception Load_cplexResult of string;
-exception Save_cplexFile of string;
-
-datatype cplexTerm = cplexVar of string
-           | cplexNum of string
-           | cplexInf
-                   | cplexNeg of cplexTerm
-                   | cplexProd of cplexTerm * cplexTerm
-                   | cplexSum of (cplexTerm list)
-datatype cplexComp = cplexLe | cplexLeq | cplexEq | cplexGe | cplexGeq
-datatype cplexGoal = cplexMinimize of cplexTerm | cplexMaximize of cplexTerm
-datatype cplexConstr = cplexConstr of cplexComp * (cplexTerm * cplexTerm)
-datatype cplexBounds = cplexBounds of cplexTerm * cplexComp * cplexTerm
-                      * cplexComp * cplexTerm
-                     | cplexBound of cplexTerm * cplexComp * cplexTerm
-datatype cplexProg = cplexProg of string
-                  * cplexGoal
-                  * ((string option * cplexConstr) list)
-                  * cplexBounds list
-
-fun rev_cmp cplexLe = cplexGe
-  | rev_cmp cplexLeq = cplexGeq
-  | rev_cmp cplexGe = cplexLe
-  | rev_cmp cplexGeq = cplexLeq
-  | rev_cmp cplexEq = cplexEq
-
-fun the NONE = raise (Load_cplexFile "SOME expected")
-  | the (SOME x) = x;
-
-fun modulo_signed is_something (cplexNeg u) = is_something u
-  | modulo_signed is_something u = is_something u
-
-fun is_Num (cplexNum _) = true
-  | is_Num _ = false
-
-fun is_Inf cplexInf = true
-  | is_Inf _ = false
-
-fun is_Var (cplexVar _) = true
-  | is_Var _ = false
-
-fun is_Neg (cplexNeg x ) = true
-  | is_Neg _ = false
-
-fun is_normed_Prod (cplexProd (t1, t2)) =
-    (is_Num t1) andalso (is_Var t2)
-  | is_normed_Prod x = is_Var x
-
-fun is_normed_Sum (cplexSum ts) =
-    (ts <> []) andalso forall (modulo_signed is_normed_Prod) ts
-  | is_normed_Sum x = modulo_signed is_normed_Prod x
-
-fun is_normed_Constr (cplexConstr (c, (t1, t2))) =
-    (is_normed_Sum t1) andalso (modulo_signed is_Num t2)
-
-fun is_Num_or_Inf x = is_Inf x orelse is_Num x
-
-fun is_normed_Bounds (cplexBounds (t1, c1, t2, c2, t3)) =
-    (c1 = cplexLe orelse c1 = cplexLeq) andalso
-    (c2 = cplexLe orelse c2 = cplexLeq) andalso
-    is_Var t2 andalso
-    modulo_signed is_Num_or_Inf t1 andalso
-    modulo_signed is_Num_or_Inf t3
-  | is_normed_Bounds (cplexBound (t1, c, t2)) =
-    (is_Var t1 andalso (modulo_signed is_Num_or_Inf t2))
-    orelse
-    (c <> cplexEq andalso
-     is_Var t2 andalso (modulo_signed is_Num_or_Inf t1))
-
-fun term_of_goal (cplexMinimize x) = x
-  | term_of_goal (cplexMaximize x) = x
-
-fun is_normed_cplexProg (cplexProg (name, goal, constraints, bounds)) =
-    is_normed_Sum (term_of_goal goal) andalso
-    forall (fn (_,x) => is_normed_Constr x) constraints andalso
-    forall is_normed_Bounds bounds
-
-fun is_NL s = s = "\n"
-
-fun is_blank s = forall (fn c => c <> #"\n" andalso Char.isSpace c) (String.explode s)
-
-fun is_num a =
-    let
-    val b = String.explode a
-    fun num4 cs = forall Char.isDigit cs
-    fun num3 [] = true
-      | num3 (ds as (c::cs)) =
-        if c = #"+" orelse c = #"-" then
-        num4 cs
-        else
-        num4 ds
-    fun num2 [] = true
-      | num2 (c::cs) =
-        if c = #"e" orelse c = #"E" then num3 cs
-        else (Char.isDigit c) andalso num2 cs
-    fun num1 [] = true
-      | num1 (c::cs) =
-        if c = #"." then num2 cs
-        else if c = #"e" orelse c = #"E" then num3 cs
-        else (Char.isDigit c) andalso num1 cs
-    fun num [] = true
-      | num (c::cs) =
-        if c = #"." then num2 cs
-        else (Char.isDigit c) andalso num1 cs
-    in
-    num b
-    end
-
-fun is_delimiter s = s = "+" orelse s = "-" orelse s = ":"
-
-fun is_cmp s = s = "<" orelse s = ">" orelse s = "<="
-             orelse s = ">=" orelse s = "="
-
-fun is_symbol a =
-    let
-    val symbol_char = String.explode "!\"#$%&()/,.;?@_`'{}|~"
-    fun is_symbol_char c = Char.isAlphaNum c orelse
-                   exists (fn d => d=c) symbol_char
-    fun is_symbol_start c = is_symbol_char c andalso
-                not (Char.isDigit c) andalso
-                not (c= #".")
-    val b = String.explode a
-    in
-    b <> [] andalso is_symbol_start (hd b) andalso
-    forall is_symbol_char b
-    end
-
-fun to_upper s = String.implode (map Char.toUpper (String.explode s))
-
-fun keyword x =
-    let
-    val a = to_upper x
-    in
-    if a = "BOUNDS" orelse a = "BOUND" then
-        SOME "BOUNDS"
-    else if a = "MINIMIZE" orelse a = "MINIMUM" orelse a = "MIN" then
-        SOME "MINIMIZE"
-    else if a = "MAXIMIZE" orelse a = "MAXIMUM" orelse a = "MAX" then
-        SOME "MAXIMIZE"
-    else if a = "ST" orelse a = "S.T." orelse a = "ST." then
-        SOME "ST"
-    else if a = "FREE" orelse a = "END" then
-        SOME a
-    else if a = "GENERAL" orelse a = "GENERALS" orelse a = "GEN" then
-        SOME "GENERAL"
-    else if a = "INTEGER" orelse a = "INTEGERS" orelse a = "INT" then
-        SOME "INTEGER"
-    else if a = "BINARY" orelse a = "BINARIES" orelse a = "BIN" then
-        SOME "BINARY"
-    else if a = "INF" orelse a = "INFINITY" then
-        SOME "INF"
-    else
-        NONE
-    end
-
-val TOKEN_ERROR = ~1
-val TOKEN_BLANK = 0
-val TOKEN_NUM = 1
-val TOKEN_DELIMITER = 2
-val TOKEN_SYMBOL = 3
-val TOKEN_LABEL = 4
-val TOKEN_CMP = 5
-val TOKEN_KEYWORD = 6
-val TOKEN_NL = 7
-
-(* tokenize takes a list of chars as argument and returns a list of
-   int * string pairs, each string representing a "cplex token",
-   and each int being one of TOKEN_NUM, TOKEN_DELIMITER, TOKEN_CMP
-   or TOKEN_SYMBOL *)
-fun tokenize s =
-    let
-    val flist = [(is_NL, TOKEN_NL),
-             (is_blank, TOKEN_BLANK),
-             (is_num, TOKEN_NUM),
-                     (is_delimiter, TOKEN_DELIMITER),
-             (is_cmp, TOKEN_CMP),
-             (is_symbol, TOKEN_SYMBOL)]
-    fun match_helper [] s = (fn x => false, TOKEN_ERROR)
-      | match_helper (f::fs) s =
-        if ((fst f) s) then f else match_helper fs s
-    fun match s = match_helper flist s
-    fun tok s =
-        if s = "" then [] else
-        let
-        val h = String.substring (s,0,1)
-        val (f, j) = match h
-        fun len i =
-            if size s = i then i
-            else if f (String.substring (s,0,i+1)) then
-            len (i+1)
-            else i
-        in
-        if j < 0 then
-            (if h = "\\" then []
-             else raise (Load_cplexFile ("token expected, found: "
-                         ^s)))
-        else
-            let
-            val l = len 1
-            val u = String.substring (s,0,l)
-            val v = String.extract (s,l,NONE)
-            in
-            if j = 0 then tok v else (j, u) :: tok v
-            end
-        end
-    in
-    tok s
-    end
-
-exception Tokenize of string;
-
-fun tokenize_general flist s =
-    let
-    fun match_helper [] s = raise (Tokenize s)
-      | match_helper (f::fs) s =
-        if ((fst f) s) then f else match_helper fs s
-    fun match s = match_helper flist s
-    fun tok s =
-        if s = "" then [] else
-        let
-        val h = String.substring (s,0,1)
-        val (f, j) = match h
-        fun len i =
-            if size s = i then i
-            else if f (String.substring (s,0,i+1)) then
-            len (i+1)
-            else i
-        val l = len 1
-        in
-        (j, String.substring (s,0,l)) :: tok (String.extract (s,l,NONE))
-        end
-    in
-    tok s
-    end
-
-fun load_cplexFile name =
-    let
-    val f = TextIO.openIn name
-        val ignore_NL = Unsynchronized.ref true
-    val rest = Unsynchronized.ref []
-
-    fun is_symbol s c = (fst c) = TOKEN_SYMBOL andalso (to_upper (snd c)) = s
-
-    fun readToken_helper () =
-        if length (!rest) > 0 then
-        let val u = hd (!rest) in
-            (
-             rest := tl (!rest);
-             SOME u
-            )
-        end
-        else
-          (case TextIO.inputLine f of
-            NONE => NONE
-          | SOME s =>
-            let val t = tokenize s in
-            if (length t >= 2 andalso
-                snd(hd (tl t)) = ":")
-            then
-                rest := (TOKEN_LABEL, snd (hd t)) :: (tl (tl t))
-            else if (length t >= 2) andalso is_symbol "SUBJECT" (hd (t))
-                andalso is_symbol "TO" (hd (tl t))
-            then
-                rest := (TOKEN_SYMBOL, "ST") :: (tl (tl t))
-            else
-                rest := t;
-            readToken_helper ()
-            end)
-
-    fun readToken_helper2 () =
-        let val c = readToken_helper () in
-            if c = NONE then NONE
-                    else if !ignore_NL andalso fst (the c) = TOKEN_NL then
-            readToken_helper2 ()
-            else if fst (the c) = TOKEN_SYMBOL
-                andalso keyword (snd (the c)) <> NONE
-            then SOME (TOKEN_KEYWORD, the (keyword (snd (the c))))
-            else c
-        end
-
-    fun readToken () = readToken_helper2 ()
-
-    fun pushToken a = rest := (a::(!rest))
-
-    fun is_value token =
-        fst token = TOKEN_NUM orelse (fst token = TOKEN_KEYWORD
-                      andalso snd token = "INF")
-
-        fun get_value token =
-        if fst token = TOKEN_NUM then
-        cplexNum (snd token)
-        else if fst token = TOKEN_KEYWORD andalso snd token = "INF"
-        then
-        cplexInf
-        else
-        raise (Load_cplexFile "num expected")
-
-    fun readTerm_Product only_num =
-        let val c = readToken () in
-        if c = NONE then NONE
-        else if fst (the c) = TOKEN_SYMBOL
-        then (
-            if only_num then (pushToken (the c); NONE)
-            else SOME (cplexVar (snd (the c)))
-            )
-        else if only_num andalso is_value (the c) then
-            SOME (get_value (the c))
-        else if is_value (the c) then
-            let val t1 = get_value (the c)
-            val d = readToken ()
-            in
-            if d = NONE then SOME t1
-            else if fst (the d) = TOKEN_SYMBOL then
-                SOME (cplexProd (t1, cplexVar (snd (the d))))
-            else
-                (pushToken (the d); SOME t1)
-            end
-        else (pushToken (the c); NONE)
-        end
-
-    fun readTerm_Signed only_signed only_num =
-        let
-        val c = readToken ()
-        in
-        if c = NONE then NONE
-        else
-            let val d = the c in
-            if d = (TOKEN_DELIMITER, "+") then
-                readTerm_Product only_num
-             else if d = (TOKEN_DELIMITER, "-") then
-                 SOME (cplexNeg (the (readTerm_Product
-                              only_num)))
-             else (pushToken d;
-                   if only_signed then NONE
-                   else readTerm_Product only_num)
-            end
-        end
-
-    fun readTerm_Sum first_signed =
-        let val c = readTerm_Signed first_signed false in
-        if c = NONE then [] else (the c)::(readTerm_Sum true)
-        end
-
-    fun readTerm () =
-        let val c = readTerm_Sum false in
-        if c = [] then NONE
-        else if tl c = [] then SOME (hd c)
-        else SOME (cplexSum c)
-        end
-
-    fun readLabeledTerm () =
-        let val c = readToken () in
-        if c = NONE then (NONE, NONE)
-        else if fst (the c) = TOKEN_LABEL then
-            let val t = readTerm () in
-            if t = NONE then
-                raise (Load_cplexFile ("term after label "^
-                           (snd (the c))^
-                           " expected"))
-            else (SOME (snd (the c)), t)
-            end
-        else (pushToken (the c); (NONE, readTerm ()))
-        end
-
-    fun readGoal () =
-        let
-        val g = readToken ()
-        in
-            if g = SOME (TOKEN_KEYWORD, "MAXIMIZE") then
-            cplexMaximize (the (snd (readLabeledTerm ())))
-        else if g = SOME (TOKEN_KEYWORD, "MINIMIZE") then
-            cplexMinimize (the (snd (readLabeledTerm ())))
-        else raise (Load_cplexFile "MAXIMIZE or MINIMIZE expected")
-        end
-
-    fun str2cmp b =
-        (case b of
-         "<" => cplexLe
-           | "<=" => cplexLeq
-           | ">" => cplexGe
-           | ">=" => cplexGeq
-               | "=" => cplexEq
-           | _ => raise (Load_cplexFile (b^" is no TOKEN_CMP")))
-
-    fun readConstraint () =
-            let
-        val t = readLabeledTerm ()
-        fun make_constraint b t1 t2 =
-                    cplexConstr
-            (str2cmp b,
-             (t1, t2))
-        in
-        if snd t = NONE then NONE
-        else
-            let val c = readToken () in
-            if c = NONE orelse fst (the c) <> TOKEN_CMP
-            then raise (Load_cplexFile "TOKEN_CMP expected")
-            else
-                let val n = readTerm_Signed false true in
-                if n = NONE then
-                    raise (Load_cplexFile "num expected")
-                else
-                    SOME (fst t,
-                      make_constraint (snd (the c))
-                              (the (snd t))
-                              (the n))
-                end
-            end
-        end
-
-        fun readST () =
-        let
-        fun readbody () =
-            let val t = readConstraint () in
-            if t = NONE then []
-            else if (is_normed_Constr (snd (the t))) then
-                (the t)::(readbody ())
-            else if (fst (the t) <> NONE) then
-                raise (Load_cplexFile
-                       ("constraint '"^(the (fst (the t)))^
-                    "'is not normed"))
-            else
-                raise (Load_cplexFile
-                       "constraint is not normed")
-            end
-        in
-        if readToken () = SOME (TOKEN_KEYWORD, "ST")
-        then
-            readbody ()
-        else
-            raise (Load_cplexFile "ST expected")
-        end
-
-    fun readCmp () =
-        let val c = readToken () in
-        if c = NONE then NONE
-        else if fst (the c) = TOKEN_CMP then
-            SOME (str2cmp (snd (the c)))
-        else (pushToken (the c); NONE)
-        end
-
-    fun skip_NL () =
-        let val c = readToken () in
-        if c <> NONE andalso fst (the c) = TOKEN_NL then
-            skip_NL ()
-        else
-            (pushToken (the c); ())
-        end
-
-    fun is_var (cplexVar _) = true
-      | is_var _ = false
-
-    fun make_bounds c t1 t2 =
-        cplexBound (t1, c, t2)
-
-    fun readBound () =
-        let
-        val _ = skip_NL ()
-        val t1 = readTerm ()
-        in
-        if t1 = NONE then NONE
-        else
-            let
-            val c1 = readCmp ()
-            in
-            if c1 = NONE then
-                let
-                val c = readToken ()
-                in
-                if c = SOME (TOKEN_KEYWORD, "FREE") then
-                    SOME (
-                    cplexBounds (cplexNeg cplexInf,
-                         cplexLeq,
-                         the t1,
-                         cplexLeq,
-                         cplexInf))
-                else
-                    raise (Load_cplexFile "FREE expected")
-                end
-            else
-                let
-                val t2 = readTerm ()
-                in
-                if t2 = NONE then
-                    raise (Load_cplexFile "term expected")
-                else
-                    let val c2 = readCmp () in
-                    if c2 = NONE then
-                        SOME (make_bounds (the c1)
-                                  (the t1)
-                                  (the t2))
-                    else
-                        SOME (
-                        cplexBounds (the t1,
-                             the c1,
-                             the t2,
-                             the c2,
-                             the (readTerm())))
-                    end
-                end
-            end
-        end
-
-    fun readBounds () =
-        let
-        fun makestring b = "?"
-        fun readbody () =
-            let
-            val b = readBound ()
-            in
-            if b = NONE then []
-            else if (is_normed_Bounds (the b)) then
-                (the b)::(readbody())
-            else (
-                raise (Load_cplexFile
-                       ("bounds are not normed in: "^
-                    (makestring (the b)))))
-            end
-        in
-        if readToken () = SOME (TOKEN_KEYWORD, "BOUNDS") then
-            readbody ()
-        else raise (Load_cplexFile "BOUNDS expected")
-        end
-
-        fun readEnd () =
-        if readToken () = SOME (TOKEN_KEYWORD, "END") then ()
-        else raise (Load_cplexFile "END expected")
-
-    val result_Goal = readGoal ()
-    val result_ST = readST ()
-    val _ =    ignore_NL := false
-        val result_Bounds = readBounds ()
-        val _ = ignore_NL := true
-        val _ = readEnd ()
-    val _ = TextIO.closeIn f
-    in
-    cplexProg (name, result_Goal, result_ST, result_Bounds)
-    end
-
-fun save_cplexFile filename (cplexProg (name, goal, constraints, bounds)) =
-    let
-    val f = TextIO.openOut filename
-
-    fun basic_write s = TextIO.output(f, s)
-
-    val linebuf = Unsynchronized.ref ""
-    fun buf_flushline s =
-        (basic_write (!linebuf);
-         basic_write "\n";
-         linebuf := s)
-    fun buf_add s = linebuf := (!linebuf) ^ s
-
-    fun write s =
-        if (String.size s) + (String.size (!linebuf)) >= 250 then
-        buf_flushline ("    "^s)
-        else
-        buf_add s
-
-        fun writeln s = (buf_add s; buf_flushline "")
-
-    fun write_term (cplexVar x) = write x
-      | write_term (cplexNum x) = write x
-      | write_term cplexInf = write "inf"
-      | write_term (cplexProd (cplexNum "1", b)) = write_term b
-      | write_term (cplexProd (a, b)) =
-        (write_term a; write " "; write_term b)
-          | write_term (cplexNeg x) = (write " - "; write_term x)
-          | write_term (cplexSum ts) = write_terms ts
-    and write_terms [] = ()
-      | write_terms (t::ts) =
-        (if (not (is_Neg t)) then write " + " else ();
-         write_term t; write_terms ts)
-
-    fun write_goal (cplexMaximize term) =
-        (writeln "MAXIMIZE"; write_term term; writeln "")
-      | write_goal (cplexMinimize term) =
-        (writeln "MINIMIZE"; write_term term; writeln "")
-
-    fun write_cmp cplexLe = write "<"
-      | write_cmp cplexLeq = write "<="
-      | write_cmp cplexEq = write "="
-      | write_cmp cplexGe = write ">"
-      | write_cmp cplexGeq = write ">="
-
-    fun write_constr (cplexConstr (cmp, (a,b))) =
-        (write_term a;
-         write " ";
-         write_cmp cmp;
-         write " ";
-         write_term b)
-
-    fun write_constraints [] = ()
-      | write_constraints (c::cs) =
-        (if (fst c <> NONE)
-         then
-         (write (the (fst c)); write ": ")
-         else
-         ();
-         write_constr (snd c);
-         writeln "";
-         write_constraints cs)
-
-    fun write_bounds [] = ()
-      | write_bounds ((cplexBounds (t1,c1,t2,c2,t3))::bs) =
-        ((if t1 = cplexNeg cplexInf andalso t3 = cplexInf
-         andalso (c1 = cplexLeq orelse c1 = cplexLe)
-         andalso (c2 = cplexLeq orelse c2 = cplexLe)
-          then
-          (write_term t2; write " free")
-          else
-          (write_term t1; write " "; write_cmp c1; write " ";
-           write_term t2; write " "; write_cmp c2; write " ";
-           write_term t3)
-         ); writeln ""; write_bounds bs)
-      | write_bounds ((cplexBound (t1, c, t2)) :: bs) =
-        (write_term t1; write " ";
-         write_cmp c; write " ";
-         write_term t2; writeln ""; write_bounds bs)
-
-    val _ = write_goal goal
-        val _ = (writeln ""; writeln "ST")
-    val _ = write_constraints constraints
-        val _ = (writeln ""; writeln "BOUNDS")
-    val _ = write_bounds bounds
-        val _ = (writeln ""; writeln "END")
-        val _ = TextIO.closeOut f
-    in
-    ()
-    end
-
-fun norm_Constr (constr as cplexConstr (c, (t1, t2))) =
-    if not (modulo_signed is_Num t2) andalso
-       modulo_signed is_Num t1
-    then
-    [cplexConstr (rev_cmp c, (t2, t1))]
-    else if (c = cplexLe orelse c = cplexLeq) andalso
-        (t1 = (cplexNeg cplexInf) orelse t2 = cplexInf)
-    then
-    []
-    else if (c = cplexGe orelse c = cplexGeq) andalso
-        (t1 = cplexInf orelse t2 = cplexNeg cplexInf)
-    then
-    []
-    else
-    [constr]
-
-fun bound2constr (cplexBounds (t1,c1,t2,c2,t3)) =
-    (norm_Constr(cplexConstr (c1, (t1, t2))))
-    @ (norm_Constr(cplexConstr (c2, (t2, t3))))
-  | bound2constr (cplexBound (t1, cplexEq, t2)) =
-    (norm_Constr(cplexConstr (cplexLeq, (t1, t2))))
-    @ (norm_Constr(cplexConstr (cplexLeq, (t2, t1))))
-  | bound2constr (cplexBound (t1, c1, t2)) =
-    norm_Constr(cplexConstr (c1, (t1,t2)))
-
-val emptyset = Symtab.empty
-
-fun singleton v = Symtab.update (v, ()) emptyset
-
-fun merge a b = Symtab.merge (op =) (a, b)
-
-fun mergemap f ts = fold (fn x => fn table => merge table (f x)) ts Symtab.empty
-
-fun diff a b = Symtab.fold (Symtab.delete_safe o fst) b a
-
-fun collect_vars (cplexVar v) = singleton v
-  | collect_vars (cplexNeg t) = collect_vars t
-  | collect_vars (cplexProd (t1, t2)) =
-    merge (collect_vars t1) (collect_vars t2)
-  | collect_vars (cplexSum ts) = mergemap collect_vars ts
-  | collect_vars _ = emptyset
-
-(* Eliminates all nonfree bounds from the linear program and produces an
-   equivalent program with only free bounds
-   IF for the input program P holds: is_normed_cplexProg P *)
-fun elim_nonfree_bounds (cplexProg (name, goal, constraints, bounds)) =
-    let
-    fun collect_constr_vars (_, cplexConstr (c, (t1,_))) =
-        (collect_vars t1)
-
-    val cvars = merge (collect_vars (term_of_goal goal))
-              (mergemap collect_constr_vars constraints)
-
-    fun collect_lower_bounded_vars
-        (cplexBounds (t1, c1, cplexVar v, c2, t3)) =
-        singleton v
-      |  collect_lower_bounded_vars
-         (cplexBound (_, cplexLe, cplexVar v)) =
-         singleton v
-      |  collect_lower_bounded_vars
-         (cplexBound (_, cplexLeq, cplexVar v)) =
-         singleton v
-      |  collect_lower_bounded_vars
-         (cplexBound (cplexVar v, cplexGe,_)) =
-         singleton v
-      |  collect_lower_bounded_vars
-         (cplexBound (cplexVar v, cplexGeq, _)) =
-         singleton v
-      | collect_lower_bounded_vars
-        (cplexBound (cplexVar v, cplexEq, _)) =
-        singleton v
-      |  collect_lower_bounded_vars _ = emptyset
-
-    val lvars = mergemap collect_lower_bounded_vars bounds
-    val positive_vars = diff cvars lvars
-    val zero = cplexNum "0"
-
-    fun make_pos_constr v =
-        (NONE, cplexConstr (cplexGeq, ((cplexVar v), zero)))
-
-    fun make_free_bound v =
-        cplexBounds (cplexNeg cplexInf, cplexLeq,
-             cplexVar v, cplexLeq,
-             cplexInf)
-
-    val pos_constrs = rev (Symtab.fold
-                  (fn (k, v) => cons (make_pos_constr k))
-                  positive_vars [])
-        val bound_constrs = map (pair NONE)
-                (maps bound2constr bounds)
-    val constraints' = constraints @ pos_constrs @ bound_constrs
-    val bounds' = rev (Symtab.fold (fn (v, _) => cons (make_free_bound v)) cvars []);
-    in
-    cplexProg (name, goal, constraints', bounds')
-    end
-
-fun relax_strict_ineqs (cplexProg (name, goals, constrs, bounds)) =
-    let
-    fun relax cplexLe = cplexLeq
-      | relax cplexGe = cplexGeq
-      | relax x = x
-
-    fun relax_constr (n, cplexConstr(c, (t1, t2))) =
-        (n, cplexConstr(relax c, (t1, t2)))
-
-    fun relax_bounds (cplexBounds (t1, c1, t2, c2, t3)) =
-        cplexBounds (t1, relax c1, t2, relax c2, t3)
-      | relax_bounds (cplexBound (t1, c, t2)) =
-        cplexBound (t1, relax c, t2)
-    in
-    cplexProg (name,
-           goals,
-           map relax_constr constrs,
-           map relax_bounds bounds)
-    end
-
-datatype cplexResult = Unbounded
-             | Infeasible
-             | Undefined
-             | Optimal of string * ((string * string) list)
-
-fun is_separator x = forall (fn c => c = #"-") (String.explode x)
-
-fun is_sign x = (x = "+" orelse x = "-")
-
-fun is_colon x = (x = ":")
-
-fun is_resultsymbol a =
-    let
-    val symbol_char = String.explode "!\"#$%&()/,.;?@_`'{}|~-"
-    fun is_symbol_char c = Char.isAlphaNum c orelse
-                   exists (fn d => d=c) symbol_char
-    fun is_symbol_start c = is_symbol_char c andalso
-                not (Char.isDigit c) andalso
-                not (c= #".") andalso
-                not (c= #"-")
-    val b = String.explode a
-    in
-    b <> [] andalso is_symbol_start (hd b) andalso
-    forall is_symbol_char b
-    end
-
-val TOKEN_SIGN = 100
-val TOKEN_COLON = 101
-val TOKEN_SEPARATOR = 102
-
-fun load_glpkResult name =
-    let
-    val flist = [(is_NL, TOKEN_NL),
-             (is_blank, TOKEN_BLANK),
-             (is_num, TOKEN_NUM),
-             (is_sign, TOKEN_SIGN),
-                     (is_colon, TOKEN_COLON),
-             (is_cmp, TOKEN_CMP),
-             (is_resultsymbol, TOKEN_SYMBOL),
-             (is_separator, TOKEN_SEPARATOR)]
-
-    val tokenize = tokenize_general flist
-
-    val f = TextIO.openIn name
-
-    val rest = Unsynchronized.ref []
-
-    fun readToken_helper () =
-        if length (!rest) > 0 then
-        let val u = hd (!rest) in
-            (
-             rest := tl (!rest);
-             SOME u
-            )
-        end
-        else
-        (case TextIO.inputLine f of
-          NONE => NONE
-        | SOME s => (rest := tokenize s; readToken_helper()))
-
-    fun is_tt tok ty = (tok <> NONE andalso (fst (the tok)) = ty)
-
-    fun pushToken a = if a = NONE then () else (rest := ((the a)::(!rest)))
-
-    fun readToken () =
-        let val t = readToken_helper () in
-        if is_tt t TOKEN_BLANK then
-            readToken ()
-        else if is_tt t TOKEN_NL then
-            let val t2 = readToken_helper () in
-            if is_tt t2 TOKEN_SIGN then
-                (pushToken (SOME (TOKEN_SEPARATOR, "-")); t)
-            else
-                (pushToken t2; t)
-            end
-        else if is_tt t TOKEN_SIGN then
-            let val t2 = readToken_helper () in
-            if is_tt t2 TOKEN_NUM then
-                (SOME (TOKEN_NUM, (snd (the t))^(snd (the t2))))
-            else
-                (pushToken t2; t)
-            end
-        else
-            t
-        end
-
-        fun readRestOfLine P =
-        let
-        val t = readToken ()
-        in
-        if is_tt t TOKEN_NL orelse t = NONE
-        then P
-        else readRestOfLine P
-        end
-
-    fun readHeader () =
-        let
-        fun readStatus () = readRestOfLine ("STATUS", snd (the (readToken ())))
-        fun readObjective () = readRestOfLine ("OBJECTIVE", snd (the (readToken (); readToken (); readToken ())))
-        val t1 = readToken ()
-        val t2 = readToken ()
-        in
-        if is_tt t1 TOKEN_SYMBOL andalso is_tt t2 TOKEN_COLON
-        then
-            case to_upper (snd (the t1)) of
-            "STATUS" => (readStatus ())::(readHeader ())
-              | "OBJECTIVE" => (readObjective())::(readHeader ())
-              | _ => (readRestOfLine (); readHeader ())
-        else
-            (pushToken t2; pushToken t1; [])
-        end
-
-    fun skip_until_sep () =
-        let val x = readToken () in
-        if is_tt x TOKEN_SEPARATOR then
-            readRestOfLine ()
-        else
-            skip_until_sep ()
-        end
-
-    fun load_value () =
-        let
-        val t1 = readToken ()
-        val t2 = readToken ()
-        in
-        if is_tt t1 TOKEN_NUM andalso is_tt t2 TOKEN_SYMBOL then
-            let
-            val t = readToken ()
-            val state = if is_tt t TOKEN_NL then readToken () else t
-            val _ = if is_tt state TOKEN_SYMBOL then () else raise (Load_cplexResult "state expected")
-            val k = readToken ()
-            in
-            if is_tt k TOKEN_NUM then
-                readRestOfLine (SOME (snd (the t2), snd (the k)))
-            else
-                raise (Load_cplexResult "number expected")
-            end
-        else
-            (pushToken t2; pushToken t1; NONE)
-        end
-
-    fun load_values () =
-        let val v = load_value () in
-        if v = NONE then [] else (the v)::(load_values ())
-        end
-
-    val header = readHeader ()
-
-    val result =
-        case AList.lookup (op =) header "STATUS" of
-        SOME "INFEASIBLE" => Infeasible
-          | SOME "UNBOUNDED" => Unbounded
-          | SOME "OPTIMAL" => Optimal (the (AList.lookup (op =) header "OBJECTIVE"),
-                       (skip_until_sep ();
-                        skip_until_sep ();
-                        load_values ()))
-          | _ => Undefined
-
-    val _ = TextIO.closeIn f
-    in
-    result
-    end
-    handle (Tokenize s) => raise (Load_cplexResult ("Tokenize: "^s))
-     | Option => raise (Load_cplexResult "Option")
-     | x => raise x
-
-fun load_cplexResult name =
-    let
-    val flist = [(is_NL, TOKEN_NL),
-             (is_blank, TOKEN_BLANK),
-             (is_num, TOKEN_NUM),
-             (is_sign, TOKEN_SIGN),
-                     (is_colon, TOKEN_COLON),
-             (is_cmp, TOKEN_CMP),
-             (is_resultsymbol, TOKEN_SYMBOL)]
-
-    val tokenize = tokenize_general flist
-
-    val f = TextIO.openIn name
-
-    val rest = Unsynchronized.ref []
-
-    fun readToken_helper () =
-        if length (!rest) > 0 then
-        let val u = hd (!rest) in
-            (
-             rest := tl (!rest);
-             SOME u
-            )
-        end
-        else
-        (case TextIO.inputLine f of
-          NONE => NONE
-        | SOME s => (rest := tokenize s; readToken_helper()))
-
-    fun is_tt tok ty = (tok <> NONE andalso (fst (the tok)) = ty)
-
-    fun pushToken a = if a = NONE then () else (rest := ((the a)::(!rest)))
-
-    fun readToken () =
-        let val t = readToken_helper () in
-        if is_tt t TOKEN_BLANK then
-            readToken ()
-        else if is_tt t TOKEN_SIGN then
-            let val t2 = readToken_helper () in
-            if is_tt t2 TOKEN_NUM then
-                (SOME (TOKEN_NUM, (snd (the t))^(snd (the t2))))
-            else
-                (pushToken t2; t)
-            end
-        else
-            t
-        end
-
-        fun readRestOfLine P =
-        let
-        val t = readToken ()
-        in
-        if is_tt t TOKEN_NL orelse t = NONE
-        then P
-        else readRestOfLine P
-        end
-
-    fun readHeader () =
-        let
-        fun readStatus () = readRestOfLine ("STATUS", snd (the (readToken ())))
-        fun readObjective () =
-            let
-            val t = readToken ()
-            in
-            if is_tt t TOKEN_SYMBOL andalso to_upper (snd (the t)) = "VALUE" then
-                readRestOfLine ("OBJECTIVE", snd (the (readToken())))
-            else
-                readRestOfLine ("OBJECTIVE_NAME", snd (the t))
-            end
-
-        val t = readToken ()
-        in
-        if is_tt t TOKEN_SYMBOL then
-            case to_upper (snd (the t)) of
-            "STATUS" => (readStatus ())::(readHeader ())
-              | "OBJECTIVE" => (readObjective ())::(readHeader ())
-              | "SECTION" => (pushToken t; [])
-              | _ => (readRestOfLine (); readHeader ())
-        else
-            (readRestOfLine (); readHeader ())
-        end
-
-    fun skip_nls () =
-        let val x = readToken () in
-        if is_tt x TOKEN_NL then
-            skip_nls ()
-        else
-            (pushToken x; ())
-        end
-
-    fun skip_paragraph () =
-        if is_tt (readToken ()) TOKEN_NL then
-        (if is_tt (readToken ()) TOKEN_NL then
-             skip_nls ()
-         else
-             skip_paragraph ())
-        else
-        skip_paragraph ()
-
-    fun load_value () =
-        let
-        val t1 = readToken ()
-        val t1 = if is_tt t1 TOKEN_SYMBOL andalso snd (the t1) = "A" then readToken () else t1
-        in
-        if is_tt t1 TOKEN_NUM then
-            let
-            val name = readToken ()
-            val status = readToken ()
-            val value = readToken ()
-            in
-            if is_tt name TOKEN_SYMBOL andalso
-               is_tt status TOKEN_SYMBOL andalso
-               is_tt value TOKEN_NUM
-            then
-                readRestOfLine (SOME (snd (the name), snd (the value)))
-            else
-                raise (Load_cplexResult "column line expected")
-            end
-        else
-            (pushToken t1; NONE)
-        end
-
-    fun load_values () =
-        let val v = load_value () in
-        if v = NONE then [] else (the v)::(load_values ())
-        end
-
-    val header = readHeader ()
-
-    val result =
-        case AList.lookup (op =) header "STATUS" of
-        SOME "INFEASIBLE" => Infeasible
-          | SOME "NONOPTIMAL" => Unbounded
-          | SOME "OPTIMAL" => Optimal (the (AList.lookup (op =) header "OBJECTIVE"),
-                       (skip_paragraph ();
-                        skip_paragraph ();
-                        skip_paragraph ();
-                        skip_paragraph ();
-                        skip_paragraph ();
-                        load_values ()))
-          | _ => Undefined
-
-    val _ = TextIO.closeIn f
-    in
-    result
-    end
-    handle (Tokenize s) => raise (Load_cplexResult ("Tokenize: "^s))
-     | Option => raise (Load_cplexResult "Option")
-     | x => raise x
-
-exception Execute of string;
-
-fun tmp_file s = Path.implode (Path.expand (File.tmp_path (Path.make [s])));
-fun wrap s = "\""^s^"\"";
-
-fun solve_glpk prog =
-    let
-    val name = LargeInt.toString (Time.toMicroseconds (Time.now ()))
-    val lpname = tmp_file (name^".lp")
-    val resultname = tmp_file (name^".txt")
-    val _ = save_cplexFile lpname prog
-    val cplex_path = getenv "GLPK_PATH"
-    val cplex = if cplex_path = "" then "glpsol" else cplex_path
-    val command = (wrap cplex)^" --lpt "^(wrap lpname)^" --output "^(wrap resultname)
-    val answer = #1 (bash_output command)
-    in
-    let
-        val result = load_glpkResult resultname
-        val _ = OS.FileSys.remove lpname
-        val _ = OS.FileSys.remove resultname
-    in
-        result
-    end
-    handle (Load_cplexResult s) => raise (Execute ("Load_cplexResult: "^s^"\nExecute: "^answer))
-         | _ => raise (Execute answer)
-    end
-
-fun solve_cplex prog =
-    let
-    fun write_script s lp r =
-        let
-        val f = TextIO.openOut s
-        val _ = TextIO.output (f, "read\n"^lp^"\noptimize\nwrite\n"^r^"\nquit")
-        val _ = TextIO.closeOut f
-        in
-        ()
-        end
-
-    val name = LargeInt.toString (Time.toMicroseconds (Time.now ()))
-    val lpname = tmp_file (name^".lp")
-    val resultname = tmp_file (name^".txt")
-    val scriptname = tmp_file (name^".script")
-    val _ = save_cplexFile lpname prog
-    val cplex_path = getenv "CPLEX_PATH"
-    val cplex = if cplex_path = "" then "cplex" else cplex_path
-    val _ = write_script scriptname lpname resultname
-    val command = (wrap cplex)^" < "^(wrap scriptname)^" > /dev/null"
-    val answer = "return code "^(Int.toString (bash command))
-    in
-    let
-        val result = load_cplexResult resultname
-        val _ = OS.FileSys.remove lpname
-        val _ = OS.FileSys.remove resultname
-        val _ = OS.FileSys.remove scriptname
-    in
-        result
-    end
-    end
-
-fun solve prog =
-    case get_solver () of
-      SOLVER_DEFAULT =>
-        (case getenv "LP_SOLVER" of
-       "CPLEX" => solve_cplex prog
-         | "GLPK" => solve_glpk prog
-         | _ => raise (Execute ("LP_SOLVER must be set to CPLEX or to GLPK")))
-    | SOLVER_CPLEX => solve_cplex prog
-    | SOLVER_GLPK => solve_glpk prog
-
-end;
-
-(*
-val demofile = "/home/obua/flyspeck/kepler/LP/cplexPent2.lp45"
-val demoout = "/home/obua/flyspeck/kepler/LP/test.out"
-val demoresult = "/home/obua/flyspeck/kepler/LP/try/test2.sol"
-
-fun loadcplex () = Cplex.relax_strict_ineqs
-           (Cplex.load_cplexFile demofile)
-
-fun writecplex lp = Cplex.save_cplexFile demoout lp
-
-fun test () =
-    let
-    val lp = loadcplex ()
-    val lp2 = Cplex.elim_nonfree_bounds lp
-    in
-    writecplex lp2
-    end
-
-fun loadresult () = Cplex.load_cplexResult demoresult;
-*)
-
-(*val prog = Cplex.load_cplexFile "/home/obua/tmp/pent/graph_0.lpt";
-val _ = Cplex.solve prog;*)