X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=ginac%2Fidx.h;h=0b31696c772840c347aa0fad1aa9e71099de93c7;hp=c760f67b4e30cd3894579a393f9ac1226a22d419;hb=2466c49d0c63f82a1b3a50a8b9d111d6b827aa41;hpb=094911eb78cacb6f2877a70c9ac74766df58ccea diff --git a/ginac/idx.h b/ginac/idx.h index c760f67b..0b31696c 100644 --- a/ginac/idx.h +++ b/ginac/idx.h @@ -3,7 +3,7 @@ * Interface to GiNaC's indices. */ /* - * 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 @@ -24,6 +24,7 @@ #define __GINAC_IDX_H__ #include "ex.h" +#include "numeric.h" namespace GiNaC { @@ -45,14 +46,18 @@ 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 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: @@ -66,21 +71,27 @@ 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(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(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(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(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) */ @@ -103,11 +114,14 @@ 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(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. */ @@ -125,15 +139,74 @@ 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 -inline const idx &ex_to_idx(const ex & e) + +/** Specialization of is_exactly_a(obj) for idx objects. */ +template<> inline bool is_exactly_a(const basic & obj) +{ + return obj.tinfo()==TINFO_idx; +} + +/** Specialization of is_exactly_a(obj) for varidx objects. */ +template<> inline bool is_exactly_a(const basic & obj) { - return static_cast(*e.bp); + return obj.tinfo()==TINFO_varidx; } -inline const varidx &ex_to_varidx(const ex & e) +/** Specialization of is_exactly_a(obj) for spinidx objects. */ +template<> inline bool is_exactly_a(const basic & obj) { - return static_cast(*e.bp); + return obj.tinfo()==TINFO_spinidx; } /** Check whether two indices form a dummy pair. */ @@ -142,6 +215,53 @@ bool is_dummy_pair(const idx & i1, const idx & i2); /** 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(); +} } // namespace GiNaC