Test/dafny1/KatzManna.dfy: Changed mocked up matrix class to use Dafny's built-in array2 class.

1 files changed, 7 insertions, 16 deletions

diff --git a/Test/dafny1/KatzManna.dfy b/Test/dafny1/KatzManna.dfy
index 0f03afec..38b2963e 100644
--- a/Test/dafny1/KatzManna.dfy
+++ b/Test/dafny1/KatzManna.dfy
@@ -45,11 +45,12 @@ method Gcd(x1: int, x2: int)
   }

 }

 

-method Determinant(X: Matrix, M: int) returns (z: int)

+method Determinant(X: array2<int>, M: int) returns (z: int)

   requires 1 <= M;

-  requires X != null && M == X.Size;

+  requires X != null && M == X.Length0 && M == X.Length1;

+  modifies X;

 {

-  var y := X.Get(1,1);

+  var y := X[1-1,1-1];

   var a := 1;

   while (a != M)

     invariant 1 <= a && a <= M;

@@ -62,24 +63,14 @@ method Determinant(X: Matrix, M: int) returns (z: int)
       while (c != a)

         invariant a <= c && c <= M;

       {

-        assume X.Get(a,a) != 0;

-        call X.Set(b, c, X.Get(b,c) - X.Get(b,a) / X.Get(a,a) * X.Get(a,c));

+        assume X[a-1,a-1] != 0;

+        X[b-1, c-1] := X[b-1,c-1] - X[b-1,a-1] / X[a-1,a-1] * X[a-1,c-1];

         c := c - 1;

       }

       b := b + 1;

     }

     a := a + 1;

-    y := y * X.Get(a,a);

+    y := y * X[a-1,a-1];

   }

   z := y;

 }

-

-class Matrix {

-  ghost var Size: int;

-  function method Get(i: int, j: int): int;

-    requires 1 <= i && i <= Size;

-    requires 1 <= j && j <= Size;

-  method Set(i: int, j: int, x: int);

-    requires 1 <= i && i <= Size;

-    requires 1 <= j && j <= Size;

-}