X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=ginac%2Ftensor.cpp;h=d16bbfce4b7949b85359f926767673c5f66c839f;hp=cf0204b56319522260d5143dc3b1aea28778c270;hb=43e0a8f5ca5e1c48cef5daaf014acdbca4e44568;hpb=745d46b8492878030cc0decd1cb9bf2de2de03ff

diff --git a/ginac/tensor.cpp b/ginac/tensor.cpp
index cf0204b5..d16bbfce 100644
--- a/ginac/tensor.cpp
+++ b/ginac/tensor.cpp
@@ -27,7 +27,9 @@
 #include "idx.h"
 #include "indexed.h"
 #include "relational.h"
+#include "lst.h"
 #include "numeric.h"
+#include "print.h"
 #include "archive.h"
 #include "utils.h"
 #include "debugmsg.h"
@@ -44,24 +46,6 @@ GINAC_IMPLEMENT_REGISTERED_CLASS(tensepsilon, tensor)
 // default constructor, destructor, copy constructor assignment operator and helpers
 //////////
 
-#define DEFAULT_DESTROY(classname) \
-void classname::destroy(bool call_parent) \
-{ \
-	if (call_parent) \
-		inherited::destroy(call_parent); \
-}
-
-#define DEFAULT_CTORS(classname) \
-classname::classname() : inherited(TINFO_##classname) \
-{ \
-	debugmsg(#classname " default constructor", LOGLEVEL_CONSTRUCT); \
-} \
-void classname::copy(const classname & other) \
-{ \
-	inherited::copy(other); \
-} \
-DEFAULT_DESTROY(classname)
-
 tensor::tensor(unsigned ti) : inherited(ti)
 {
 	debugmsg("tensor constructor from unsigned", LOGLEVEL_CONSTRUCT); \
@@ -114,23 +98,6 @@ void tensepsilon::copy(const tensepsilon & other)
 // archiving
 //////////
 
-#define DEFAULT_UNARCHIVE(classname) \
-ex classname::unarchive(const archive_node &n, const lst &sym_lst) \
-{ \
-	return (new classname(n, sym_lst))->setflag(status_flags::dynallocated); \
-}
-
-#define DEFAULT_ARCHIVING(classname) \
-classname::classname(const archive_node &n, const lst &sym_lst) : inherited(n, sym_lst) \
-{ \
-	debugmsg(#classname " constructor from archive_node", LOGLEVEL_CONSTRUCT); \
-} \
-DEFAULT_UNARCHIVE(classname) \
-void classname::archive(archive_node &n) const \
-{ \
-	inherited::archive(n); \
-}
-
 DEFAULT_ARCHIVING(tensor)
 DEFAULT_ARCHIVING(tensdelta)
 DEFAULT_ARCHIVING(tensmetric)
@@ -167,13 +134,6 @@ void tensepsilon::archive(archive_node &n) const
 // functions overriding virtual functions from bases classes
 //////////
 
-#define DEFAULT_COMPARE(classname) \
-int classname::compare_same_type(const basic & other) const \
-{ \
-	/* by default, two tensors of the same class are always identical */ \
-	return 0; \
-}
-
 DEFAULT_COMPARE(tensor)
 DEFAULT_COMPARE(tensdelta)
 DEFAULT_COMPARE(tensmetric)
@@ -202,29 +162,10 @@ int tensepsilon::compare_same_type(const basic & other) const
 		return inherited::compare_same_type(other);
 }
 
-void tensdelta::print(std::ostream & os, unsigned upper_precedence) const
-{
-	debugmsg("tensdelta print",LOGLEVEL_PRINT);
-	os << "delta";
-}
-
-void tensmetric::print(std::ostream & os, unsigned upper_precedence) const
-{
-	debugmsg("tensmetric print",LOGLEVEL_PRINT);
-	os << "g";
-}
-
-void minkmetric::print(std::ostream & os, unsigned upper_precedence) const
-{
-	debugmsg("minkmetric print",LOGLEVEL_PRINT);
-	os << "eta";
-}
-
-void tensepsilon::print(std::ostream & os, unsigned upper_precedence) const
-{
-	debugmsg("tensepsilon print",LOGLEVEL_PRINT);
-	os << "eps";
-}
+DEFAULT_PRINT(tensdelta, "delta")
+DEFAULT_PRINT(tensmetric, "g")
+DEFAULT_PRINT(minkmetric, "eta")
+DEFAULT_PRINT(tensepsilon, "eps")
 
 /** Automatic symbolic evaluation of an indexed delta tensor. */
 ex tensdelta::eval_indexed(const basic & i) const
@@ -240,6 +181,15 @@ ex tensdelta::eval_indexed(const basic & i) const
 	if (is_dummy_pair(i1, i2))
 		return i1.get_dim();
 
+	// Numeric evaluation
+	if (static_cast<const indexed &>(i).all_index_values_are(info_flags::integer)) {
+		int n1 = ex_to_numeric(i1.get_value()).to_int(), n2 = ex_to_numeric(i2.get_value()).to_int();
+		if (n1 == n2)
+			return _ex1();
+		else
+			return _ex0();
+	}
+
 	// No further simplifications
 	return i.hold();
 }
@@ -308,7 +258,7 @@ ex tensepsilon::eval_indexed(const basic & i) const
 
 		// Get sign of index permutation (the indices should already be in
 		// a canonic order but we can't assume what exactly that order is)
-		vector<int> v;
+		std::vector<int> v;
 		v.reserve(i.nops() - 1);
 		for (unsigned j=1; j<i.nops(); j++)
 			v.push_back(ex_to_numeric(ex_to_idx(i.op(j)).get_value()).to_int());
@@ -385,7 +335,7 @@ bool tensmetric::contract_with(exvector::iterator self, exvector::iterator other
 
 	// If contracting with the delta tensor, let the delta do it
 	// (don't raise/lower delta indices)
-	if (is_ex_exactly_of_type(other->op(0), tensdelta))
+	if (is_ex_of_type(other->op(0), tensdelta))
 		return false;
 
 	// Try to contract first index
@@ -437,7 +387,7 @@ ex metric_tensor(const ex & i1, const ex & i2)
 	if (!is_ex_of_type(i1, varidx) || !is_ex_of_type(i2, varidx))
 		throw(std::invalid_argument("indices of metric tensor must be of type varidx"));
 
-	return indexed(tensmetric(), i1, i2);
+	return indexed(tensmetric(), indexed::symmetric, i1, i2);
 }
 
 ex lorentz_g(const ex & i1, const ex & i2, bool pos_sig)
@@ -490,4 +440,16 @@ ex lorentz_eps(const ex & i1, const ex & i2, const ex & i3, const ex & i4, bool
 	return indexed(tensepsilon(true, pos_sig), indexed::antisymmetric, i1, i2, i3, i4);
 }
 
+ex eps0123(const ex & i1, const ex & i2, const ex & i3, const ex & i4, bool pos_sig)
+{
+	if (!is_ex_of_type(i1, varidx) || !is_ex_of_type(i2, varidx) || !is_ex_of_type(i3, varidx) || !is_ex_of_type(i4, varidx))
+		throw(std::invalid_argument("indices of epsilon tensor must be of type varidx"));
+
+	ex dim = ex_to_idx(i1).get_dim();
+	if (dim.is_equal(4))
+		return lorentz_eps(i1, i2, i3, i4, pos_sig);
+	else
+		return indexed(tensepsilon(true, pos_sig), indexed::antisymmetric, i1, i2, i3, i4);
+}
+
 } // namespace GiNaC