* Interface to GiNaC's indices. */
/*
- * GiNaC Copyright (C) 1999-2001 Johannes Gutenberg University Mainz, Germany
+ * GiNaC Copyright (C) 1999-2003 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
#define __GINAC_IDX_H__
#include "ex.h"
+#include "numeric.h"
namespace GiNaC {
* @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 printraw(std::ostream & os) const;
- void printtree(std::ostream & os, unsigned indent) const;
- void print(std::ostream & os, unsigned upper_precedence=0) const;
+ 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:
ex get_value(void) const {return value;}
/** Check whether the index is numeric. */
- bool is_numeric(void) const {return is_ex_exactly_of_type(value, numeric);}
+ bool is_numeric(void) const {return is_exactly_a<numeric>(value);}
/** Check whether the index is symbolic. */
- bool is_symbolic(void) const {return !is_ex_exactly_of_type(value, numeric);}
+ bool is_symbolic(void) const {return !is_exactly_a<numeric>(value);}
/** Get dimension of index space. */
ex get_dim(void) const {return dim;}
/** Check whether the dimension is numeric. */
- bool is_dim_numeric(void) const {return is_ex_exactly_of_type(dim, numeric);}
+ bool is_dim_numeric(void) const {return is_exactly_a<numeric>(dim);}
/** Check whether the dimension is symbolic. */
- bool is_dim_symbolic(void) const {return !is_ex_exactly_of_type(dim, numeric);}
+ bool is_dim_symbolic(void) const {return !is_exactly_a<numeric>(dim);}
+
+ /** Make a new index with the same value but a different dimension. */
+ ex replace_dim(const ex & new_dim) const;
+
+ /** Return the minimum of the dimensions of this and another index.
+ * If this is undecidable, throw an exception. */
+ ex minimal_dim(const idx & other) const;
- // member variables
protected:
ex value; /**< Expression that constitutes the index (numeric or symbolic name) */
ex dim; /**< Dimension of space (can be symbolic or numeric) */
* @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(std::ostream & os, unsigned upper_precedence=0) const;
+ 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. */
};
+/** 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
-inline const idx &ex_to_idx(const ex & e)
+
+/** Specialization of is_exactly_a<idx>(obj) for idx objects. */
+template<> inline bool is_exactly_a<idx>(const basic & obj)
{
- return static_cast<const idx &>(*e.bp);
+ return obj.tinfo()==TINFO_idx;
}
-inline const varidx &ex_to_varidx(const ex & e)
+/** Specialization of is_exactly_a<varidx>(obj) for varidx objects. */
+template<> inline bool is_exactly_a<varidx>(const basic & obj)
{
- return static_cast<const varidx &>(*e.bp);
+ 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. */
/** Check whether two expressions form a dummy index pair. */
bool is_dummy_pair(const ex & e1, const ex & e2);
+/** Given a vector of indices, split them into two vectors, one containing
+ * the free indices, the other containing the dummy indices (numeric
+ * indices are neither free nor dummy ones).
+ *
+ * @param it Pointer to start of index vector
+ * @param itend Pointer to end of index vector
+ * @param out_free Vector of free indices (returned, sorted)
+ * @param out_dummy Vector of dummy indices (returned, sorted) */
+void find_free_and_dummy(exvector::const_iterator it, exvector::const_iterator itend, exvector & out_free, exvector & out_dummy);
+
+/** Given a vector of indices, split them into two vectors, one containing
+ * the free indices, the other containing the dummy indices (numeric
+ * indices are neither free nor dummy ones).
+ *
+ * @param v Index vector
+ * @param out_free Vector of free indices (returned, sorted)
+ * @param out_dummy Vector of dummy indices (returned, sorted) */
+inline void find_free_and_dummy(const exvector & v, exvector & out_free, exvector & out_dummy)
+{
+ find_free_and_dummy(v.begin(), v.end(), out_free, out_dummy);
+}
+
+/** Given a vector of indices, find the dummy indices.
+ *
+ * @param v Index vector
+ * @param out_dummy Vector of dummy indices (returned, sorted) */
+inline void find_dummy_indices(const exvector & v, exvector & out_dummy)
+{
+ exvector free_indices;
+ find_free_and_dummy(v.begin(), v.end(), free_indices, out_dummy);
+}
+
+/** Count the number of dummy index pairs in an index vector. */
+inline unsigned count_dummy_indices(const exvector & v)
+{
+ exvector free_indices, dummy_indices;
+ find_free_and_dummy(v.begin(), v.end(), free_indices, dummy_indices);
+ return dummy_indices.size();
+}
+
+/** Count the number of dummy index pairs in an index vector. */
+inline unsigned count_free_indices(const exvector & v)
+{
+ exvector free_indices, dummy_indices;
+ find_free_and_dummy(v.begin(), v.end(), free_indices, dummy_indices);
+ return free_indices.size();
+}
+
+/** Return the minimum of two index dimensions. If this is undecidable,
+ * throw an exception. Numeric dimensions are always considered "smaller"
+ * than symbolic dimensions. */
+ex minimal_dim(const ex & dim1, const ex & dim2);
} // namespace GiNaC
git://www.ginac.de / ginac.git / blobdiff