Fix bug with PolyIndex and Variable.to_repr

2 files changed, 4 insertions, 4 deletions

diff --git a/mdpoly/leaves.py b/mdpoly/leaves.py
index 4032ead..8a018e6 100644
--- a/mdpoly/leaves.py
+++ b/mdpoly/leaves.py
@@ -49,7 +49,7 @@ class Var(Leaf, HasRepr):
 
     def to_repr(self, repr_type: type[T], state: State) -> T:
         r = repr_type()
-        idx = PolyVarIndex(varindex=state.index(self), power=1)
+        idx = PolyVarIndex.of_var(self, state),
         r.set(MatrixIndex.scalar, PolyIndex(idx), 1)
         return r, state
 
diff --git a/mdpoly/types.py b/mdpoly/types.py
index a0ea671..0a4c68e 100644
--- a/mdpoly/types.py
+++ b/mdpoly/types.py
@@ -70,18 +70,18 @@ class PolyVarIndex(NamedTuple):
 
     Concretely this represents things like x^2, y^4
     """
-    varindex: int
+    var_idx: int # Index in State.variables, not variable!
     power: Number
 
     @classmethod
     @property
     def constant(cls):
         """ Special index for constants, which have no variable """
-        return cls(varindex=-1, power=0)
+        return cls(var_idx=-1, power=0)
 
     @classmethod
     def of_var(cls, variable: Var, state: State, power: Number =1) -> Self:
-        return cls(varindex=state.index(variable), power=power)
+        return cls(var_idx=state.index(variable), power=power)
 
 
 class PolyIndex(tuple[PolyVarIndex]):