- color and clifford classes are quite functional now

[ginac.git] / ginac / tensor.h

diff --git a/ginac/tensor.h b/ginac/tensor.h
index b077ee4d0c927d8e459250bb0092773b8c876163..5698b9b944450e44852b3571cb610dd0051b95ec 100644 (file)
--- a/ginac/tensor.h
+++ b/ginac/tensor.h
@@ -97,6 +97,22 @@ private:
 };
 
 
 };
 
 

+/** This class represents an antisymmetric spinor metric tensor which
+ *  can be used to raise/lower indices of 2-component Weyl spinors. If
+ *  indexed, it must have exactly two indices of the same type which
+ *  must be of class spinidx or a subclass and have dimension 2. */
+class spinmetric : public tensmetric
+{
+       GINAC_DECLARE_REGISTERED_CLASS(spinmetric, tensmetric)
+
+       // functions overriding virtual functions from bases classes
+public:
+       void print(const print_context & c, unsigned level = 0) const;
+       ex eval_indexed(const basic & i) const;
+       bool contract_with(exvector::iterator self, exvector::iterator other, exvector & v) const;
+};
+
+

 /** This class represents the totally antisymmetric epsilon tensor. If
  *  indexed, all indices must be of the same type and their number must
  *  be equal to the dimension of the index space. */
 /** This class represents the totally antisymmetric epsilon tensor. If
  *  indexed, all indices must be of the same type and their number must
  *  be equal to the dimension of the index space. */


@@ -155,6 +171,16 @@ ex metric_tensor(const ex & i1, const ex & i2);
  *  @return newly constructed Lorentz metric tensor */
 ex lorentz_g(const ex & i1, const ex & i2, bool pos_sig = false);
 
  *  @return newly constructed Lorentz metric tensor */
 ex lorentz_g(const ex & i1, const ex & i2, bool pos_sig = false);
 

+/** Create a spinor metric tensor with specified indices. The indices must be
+ *  of class spinidx or a subclass and have a dimension of 2. The spinor
+ *  metric is an antisymmetric tensor with a matrix representation of
+ *  [[ [[ 0, 1 ]], [[ -1, 0 ]] ]].
+ *
+ *  @param i1 First index
+ *  @param i2 Second index
+ *  @return newly constructed spinor metric tensor */
+ex spinor_metric(const ex & i1, const ex & i2);
+

 /** Create an epsilon tensor in a Euclidean space with two indices. The
  *  indices must be of class idx or a subclass, and have a dimension of 2.
  *
 /** Create an epsilon tensor in a Euclidean space with two indices. The
  *  indices must be of class idx or a subclass, and have a dimension of 2.
  *