- color and clifford classes are quite functional now

[ginac.git] / ginac / idx.h

diff --git a/ginac/idx.h b/ginac/idx.h
index 4981fefca4be57de67c165e6b2faeb57b12b7c54..07ff839202acf8584915bc9ed537d6059e00df49 100644 (file)
--- a/ginac/idx.h
+++ b/ginac/idx.h
@@ -124,6 +124,53 @@ protected:
 };
 
 
 };
 
 

+/** This class holds a spinor index that can be dotted or undotted and that
+ *  also has a variance. This is used in the Weyl-van-der-Waerden formalism
+ *  where the dot indicates complex conjugation. There is an associated
+ *  (asymmetric) metric tensor that can be used to raise/lower spinor
+ *  indices. */
+class spinidx : public varidx
+{
+       GINAC_DECLARE_REGISTERED_CLASS(spinidx, varidx)
+
+       // other constructors
+public:
+       /** Construct index with given value, dimension, variance and dot.
+        *
+        *  @param v Value of index (numeric or symbolic)
+        *  @param dim Dimension of index space (numeric or symbolic)
+        *  @param covariant Make covariant index (default is contravariant)
+        *  @param dotted Make covariant dotted (default is undotted)
+        *  @return newly constructed index */
+       spinidx(const ex & v, const ex & dim = 2, bool covariant = false, bool dotted = false);
+
+       // functions overriding virtual functions from bases classes
+public:
+       void print(const print_context & c, unsigned level = 0) const;
+       bool is_dummy_pair_same_type(const basic & other) const;
+
+       // non-virtual functions in this class
+public:
+       /** Check whether the index is dotted. */
+       bool is_dotted(void) const {return dotted;}
+
+       /** Check whether the index is not dotted. */
+       bool is_undotted(void) const {return !dotted;}
+
+       /** Make a new index with the same value and variance but the opposite
+        *  dottedness. */
+       ex toggle_dot(void) const;
+
+       /** Make a new index with the same value but opposite variance and
+        *  dottedness. */
+       ex toggle_variance_dot(void) const;
+
+       // member variables
+protected:
+       bool dotted;
+};
+
+

 // utility functions
 inline const idx &ex_to_idx(const ex & e)
 {
 // utility functions
 inline const idx &ex_to_idx(const ex & e)
 {


@@ -135,6 +182,11 @@ inline const varidx &ex_to_varidx(const ex & e)
        return static_cast<const varidx &>(*e.bp);
 }
 
        return static_cast<const varidx &>(*e.bp);
 }
 

+inline const spinidx &ex_to_spinidx(const ex & e)
+{
+       return static_cast<const spinidx &>(*e.bp);
+}
+

 /** Check whether two indices form a dummy pair. */
 bool is_dummy_pair(const idx & i1, const idx & i2);
 
 /** Check whether two indices form a dummy pair. */
 bool is_dummy_pair(const idx & i1, const idx & i2);