* Interface to GiNaC's indexed expressions. */
/*
- * GiNaC Copyright (C) 1999-2001 Johannes Gutenberg University Mainz, Germany
+ * GiNaC Copyright (C) 1999-2002 Johannes Gutenberg University Mainz, Germany
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
class scalar_products;
+class symmetry;
/** This class holds an indexed expression. It consists of a 'base' expression
* (the expression being indexed) which can be accessed as op(0), and n (n >= 0)
friend ex simplify_indexed(const ex & e, exvector & free_indices, exvector & dummy_indices, const scalar_products & sp);
friend ex simplify_indexed_product(const ex & e, exvector & free_indices, exvector & dummy_indices, const scalar_products & sp);
-
- // types
-public:
- /** Type of symmetry of the object with respect to commutation of its indices. */
- typedef enum {
- unknown, /**< symmetry properties unknown */
- symmetric, /**< totally symmetric */
- antisymmetric, /**< totally antisymmetric */
- mixed /**< mixed symmetry (unimplemented) */
- } symmetry_type;
+ friend bool reposition_dummy_indices(ex & e, exvector & variant_dummy_indices, exvector & moved_indices);
// other constructors
public:
* @param i1 First index
* @param i2 Second index
* @return newly constructed indexed object */
- indexed(const ex & b, symmetry_type symm, const ex & i1, const ex & i2);
+ indexed(const ex & b, const symmetry & symm, const ex & i1, const ex & i2);
/** Construct indexed object with three indices and a specified symmetry.
* The indices must be of class idx.
* @param i2 Second index
* @param i3 Third index
* @return newly constructed indexed object */
- indexed(const ex & b, symmetry_type symm, const ex & i1, const ex & i2, const ex & i3);
+ indexed(const ex & b, const symmetry & symm, const ex & i1, const ex & i2, const ex & i3);
/** Construct indexed object with four indices and a specified symmetry. The
* indices must be of class idx.
* @param i3 Third index
* @param i4 Fourth index
* @return newly constructed indexed object */
- indexed(const ex & b, symmetry_type symm, const ex & i1, const ex & i2, const ex & i3, const ex & i4);
+ indexed(const ex & b, const symmetry & symm, const ex & i1, const ex & i2, const ex & i3, const ex & i4);
/** Construct indexed object with a specified vector of indices. The indices
* must be of class idx.
* @param symm Symmetry of indices
* @param iv Vector of indices
* @return newly constructed indexed object */
- indexed(const ex & b, symmetry_type symm, const exvector & iv);
+ indexed(const ex & b, const symmetry & symm, const exvector & iv);
// internal constructors
- indexed(symmetry_type symm, const exprseq & es);
- indexed(symmetry_type symm, const exvector & v, bool discardable = false);
- indexed(symmetry_type symm, exvector * vp); // vp will be deleted
+ indexed(const symmetry & symm, const exprseq & es);
+ indexed(const symmetry & symm, const exvector & v, bool discardable = false);
+ indexed(const symmetry & symm, exvector * vp); // vp will be deleted
// functions overriding virtual functions from base classes
public:
void print(const print_context & c, unsigned level = 0) const;
bool info(unsigned inf) const;
ex eval(int level = 0) const;
- int degree(const ex & s) const;
- int ldegree(const ex & s) const;
- ex coeff(const ex & s, int n = 1) const;
exvector get_free_indices(void) const;
protected:
+ ex derivative(const symbol & s) const;
ex thisexprseq(const exvector & v) const;
ex thisexprseq(exvector * vp) const;
unsigned return_type(void) const { return return_types::commutative; }
* another indexed object. */
exvector get_dummy_indices(const indexed & other) const;
+ /** Check whether the object has an index that forms a dummy index pair
+ * with a given index. */
+ bool has_dummy_index_for(const ex & i) const;
+
+ /** Return symmetry properties. */
+ ex get_symmetry(void) const {return symtree;}
+
protected:
void printindices(const print_context & c, unsigned level) const;
- void assert_all_indices_of_type_idx(void) const;
+ void validate(void) const;
// member variables
protected:
- symmetry_type symmetry; /**< Index symmetry */
+ ex symtree; /**< Index symmetry (tree of symmetry objects) */
};
// utility functions
-inline const indexed &ex_to_indexed(const ex &e)
+
+/** Specialization of is_exactly_a<indexed>(obj) for indexed objects. */
+template<> inline bool is_exactly_a<indexed>(const basic & obj)
{
- return static_cast<const indexed &>(*e.bp);
+ return obj.tinfo()==TINFO_indexed;
}
-
-/** Simplify/canonicalize expression containing indexed objects. This
- * performs contraction of dummy indices where possible and checks whether
- * the free indices in sums are consistent.
- *
- * @param e The expression to be simplified
- * @return simplified expression */
-ex simplify_indexed(const ex & e);
-
-/** Simplify/canonicalize expression containing indexed objects. This
- * performs contraction of dummy indices where possible, checks whether
- * the free indices in sums are consistent, and automatically replaces
- * scalar products by known values if desired.
- *
- * @param e The expression to be simplified
- * @param sp Scalar products to be replaced automatically
- * @return simplified expression */
-ex simplify_indexed(const ex & e, const scalar_products & sp);
-
-
} // namespace GiNaC
#endif // ndef __GINAC_INDEXED_H__