- symmetrize eta(x,y).

[ginac.git] / ginac / idx.h

diff --git a/ginac/idx.h b/ginac/idx.h
index 4981fefca4be57de67c165e6b2faeb57b12b7c54..c2ac972108ecf1c22e4402259a9ff5af4d783327 100644 (file)
--- a/ginac/idx.h
+++ b/ginac/idx.h
@@ -45,14 +45,18 @@ public:
         *  @return newly constructed index */
        explicit idx(const ex & v, const ex & dim);
 
-       // functions overriding virtual functions from bases classes
+       // functions overriding virtual functions from base classes
 public:
        void print(const print_context & c, unsigned level = 0) const;
        bool info(unsigned inf) const;
        unsigned nops() const;
        ex & let_op(int i);
+       ex evalf(int level = 0) const;
+       ex subs(const lst & ls, const lst & lr, bool no_pattern = false) const;
+
 protected:
-       ex subs(const lst & ls, const lst & lr) const;
+       ex derivative(const symbol & s) const;
+       bool match_same_type(const basic & other) const;
 
        // new virtual functions in this class
 public:
@@ -102,11 +106,14 @@ public:
         *  @return newly constructed index */
        varidx(const ex & v, const ex & dim, bool covariant = false);
 
-       // functions overriding virtual functions from bases classes
+       // functions overriding virtual functions from base classes
 public:
        void print(const print_context & c, unsigned level = 0) const;
        bool is_dummy_pair_same_type(const basic & other) const;
 
+protected:
+       bool match_same_type(const basic & other) const;
+
        // non-virtual functions in this class
 public:
        /** Check whether the index is covariant. */
@@ -124,17 +131,97 @@ 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 base classes
+public:
+       void print(const print_context & c, unsigned level = 0) const;
+       bool is_dummy_pair_same_type(const basic & other) const;
+
+protected:
+       bool match_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
+
+/** Return the idx object handled by an ex.  Deprecated: use ex_to<idx>().
+ *  This is unsafe: you need to check the type first. */
 inline const idx &ex_to_idx(const ex & e)
 {
        return static_cast<const idx &>(*e.bp);
 }
 
+/** Return the varidx object handled by an ex.  Deprecated: use ex_to<varidx>().
+ *  This is unsafe: you need to check the type first. */
 inline const varidx &ex_to_varidx(const ex & e)
 {
        return static_cast<const varidx &>(*e.bp);
 }
 
+/** Return the spinidx object handled by an ex.  Deprecated: use ex_to<spinidx>().
+ *  This is unsafe: you need to check the type first. */
+inline const spinidx &ex_to_spinidx(const ex & e)
+{
+       return static_cast<const spinidx &>(*e.bp);
+}
+
+/** Specialization of is_exactly_a<idx>(obj) for idx objects. */
+template<> inline bool is_exactly_a<idx>(const basic & obj)
+{
+        return obj.tinfo()==TINFO_idx;
+}
+
+/** Specialization of is_exactly_a<varidx>(obj) for varidx objects. */
+template<> inline bool is_exactly_a<varidx>(const basic & obj)
+{
+        return obj.tinfo()==TINFO_varidx;
+}
+
+/** Specialization of is_exactly_a<spinidx>(obj) for spinidx objects. */
+template<> inline bool is_exactly_a<spinidx>(const basic & obj)
+{
+        return obj.tinfo()==TINFO_spinidx;
+}
+
 /** Check whether two indices form a dummy pair. */
 bool is_dummy_pair(const idx & i1, const idx & i2);
 
@@ -189,10 +276,6 @@ inline unsigned count_free_indices(const exvector & v)
        return free_indices.size();
 }
 
-/** Given two index vectors, find those indices that appear in the first
- *  vector but not in the second one (asymmetric set difference). */
-exvector index_set_difference(const exvector & set1, const exvector & set2);
-
 } // namespace GiNaC
 
 #endif // ndef __GINAC_IDX_H__