fix tosamering for inexact fields

Author: pzinn

M2/Macaulay2/m2/matrix.m2

@@ -12,9 +12,11 @@ nottosamering := (X,Y) -> (
      else error("expected ",synonym X," and ",synonym Y," for compatible rings"))
 tosamering = (M,N) -> (
      R := ring M; S := ring N;
+     R' := if instance(R,InexactField) then ring R else R;
+     S' := if instance(S,InexactField) then ring S else S;
      if R =!= S then (
-	 if isPromotable(R,S) then (promote(M,S),N)
-	 else if isPromotable(S,R) then (M,promote(N,R))
+	 if isPromotable(R',S) then (promote(M,S),N)
+	 else if isPromotable(S',R) then (M,promote(N,R))
 	 else nottosamering(class M,class N)
 	 )
      else (M,N))

M2/Macaulay2/m2/reals.m2

@@ -475,6 +475,10 @@ BesselY = method()
 BesselY(ZZ, Number) := (n, x) -> BesselY'(n, numeric x)
 BesselY(Number, Number) := (n, x) -> BesselY'(numeric n, numeric x)
 
+ring ComplexField := R -> CC
+ring RealField := R -> RR
+ring RealIntervalField := R -> RRi
+
 -- Local Variables:
 -- compile-command: "make -C $M2BUILDDIR/Macaulay2/m2 "
 -- End: