- color and clifford classes are quite functional now

[ginac.git] / ginac / tensor.cpp

diff --git a/ginac/tensor.cpp b/ginac/tensor.cpp
index 0e6b116250e69281283c012650dc674253c2ff97..23be5b0bed201caf8c465dca33be7bcaa1ef746f 100644 (file)
--- a/ginac/tensor.cpp
+++ b/ginac/tensor.cpp
@@ -27,7 +27,9 @@
 #include "idx.h"
 #include "indexed.h"
 #include "relational.h"
 #include "idx.h"
 #include "indexed.h"
 #include "relational.h"

+#include "lst.h"

 #include "numeric.h"
 #include "numeric.h"

+#include "print.h"

 #include "archive.h"
 #include "utils.h"
 #include "debugmsg.h"
 #include "archive.h"
 #include "utils.h"
 #include "debugmsg.h"


@@ -38,30 +40,13 @@ GINAC_IMPLEMENT_REGISTERED_CLASS(tensor, basic)
 GINAC_IMPLEMENT_REGISTERED_CLASS(tensdelta, tensor)
 GINAC_IMPLEMENT_REGISTERED_CLASS(tensmetric, tensor)
 GINAC_IMPLEMENT_REGISTERED_CLASS(minkmetric, tensmetric)
 GINAC_IMPLEMENT_REGISTERED_CLASS(tensdelta, tensor)
 GINAC_IMPLEMENT_REGISTERED_CLASS(tensmetric, tensor)
 GINAC_IMPLEMENT_REGISTERED_CLASS(minkmetric, tensmetric)

+GINAC_IMPLEMENT_REGISTERED_CLASS(spinmetric, tensmetric)

 GINAC_IMPLEMENT_REGISTERED_CLASS(tensepsilon, tensor)
 
 //////////
 // default constructor, destructor, copy constructor assignment operator and helpers
 //////////
 
 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); \
 tensor::tensor(unsigned ti) : inherited(ti)
 {
        debugmsg("tensor constructor from unsigned", LOGLEVEL_CONSTRUCT); \


@@ -70,6 +55,8 @@ tensor::tensor(unsigned ti) : inherited(ti)
 DEFAULT_CTORS(tensor)
 DEFAULT_CTORS(tensdelta)
 DEFAULT_CTORS(tensmetric)
 DEFAULT_CTORS(tensor)
 DEFAULT_CTORS(tensdelta)
 DEFAULT_CTORS(tensmetric)

+DEFAULT_COPY(spinmetric)
+DEFAULT_DESTROY(spinmetric)

 DEFAULT_DESTROY(minkmetric)
 DEFAULT_DESTROY(tensepsilon)
 
 DEFAULT_DESTROY(minkmetric)
 DEFAULT_DESTROY(tensepsilon)
 


@@ -79,6 +66,12 @@ minkmetric::minkmetric() : pos_sig(false)
        tinfo_key = TINFO_minkmetric;
 }
 
        tinfo_key = TINFO_minkmetric;
 }
 

+spinmetric::spinmetric()
+{
+       debugmsg("spinmetric default constructor", LOGLEVEL_CONSTRUCT);
+       tinfo_key = TINFO_spinmetric;
+}
+

 minkmetric::minkmetric(bool ps) : pos_sig(ps)
 {
        debugmsg("minkmetric constructor from bool", LOGLEVEL_CONSTRUCT);
 minkmetric::minkmetric(bool ps) : pos_sig(ps)
 {
        debugmsg("minkmetric constructor from bool", LOGLEVEL_CONSTRUCT);


@@ -114,26 +107,10 @@ void tensepsilon::copy(const tensepsilon & other)
 // archiving
 //////////
 
 // 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)
 DEFAULT_ARCHIVING(tensor)
 DEFAULT_ARCHIVING(tensdelta)
 DEFAULT_ARCHIVING(tensmetric)

+DEFAULT_ARCHIVING(spinmetric)

 DEFAULT_UNARCHIVE(minkmetric)
 DEFAULT_UNARCHIVE(tensepsilon)
 
 DEFAULT_UNARCHIVE(minkmetric)
 DEFAULT_UNARCHIVE(tensepsilon)
 


@@ -167,16 +144,10 @@ void tensepsilon::archive(archive_node &n) const
 // functions overriding virtual functions from bases classes
 //////////
 
 // 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)
 DEFAULT_COMPARE(tensor)
 DEFAULT_COMPARE(tensdelta)
 DEFAULT_COMPARE(tensmetric)

+DEFAULT_COMPARE(spinmetric)

 
 int minkmetric::compare_same_type(const basic & other) const
 {
 
 int minkmetric::compare_same_type(const basic & other) const
 {


@@ -202,29 +173,11 @@ int tensepsilon::compare_same_type(const basic & other) const
                return inherited::compare_same_type(other);
 }
 
                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_LATEX(tensdelta, "delta", "\\delta")
+DEFAULT_PRINT(tensmetric, "g")
+DEFAULT_PRINT_LATEX(minkmetric, "eta", "\\eta")
+DEFAULT_PRINT_LATEX(spinmetric, "eps", "\\varepsilon")
+DEFAULT_PRINT_LATEX(tensepsilon, "eps", "\\varepsilon")

 
 /** Automatic symbolic evaluation of an indexed delta tensor. */
 ex tensdelta::eval_indexed(const basic & i) const
 
 /** Automatic symbolic evaluation of an indexed delta tensor. */
 ex tensdelta::eval_indexed(const basic & i) const


@@ -240,6 +193,15 @@ ex tensdelta::eval_indexed(const basic & i) const
        if (is_dummy_pair(i1, i2))
                return i1.get_dim();
 
        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();
 }
        // No further simplifications
        return i.hold();
 }


@@ -292,6 +254,37 @@ ex minkmetric::eval_indexed(const basic & i) const
        return inherited::eval_indexed(i);
 }
 
        return inherited::eval_indexed(i);
 }
 

+/** Automatic symbolic evaluation of an indexed metric tensor. */
+ex spinmetric::eval_indexed(const basic & i) const
+{
+       GINAC_ASSERT(is_of_type(i, indexed));
+       GINAC_ASSERT(i.nops() == 3);
+       GINAC_ASSERT(is_ex_of_type(i.op(0), spinmetric));
+       GINAC_ASSERT(is_ex_of_type(i.op(1), spinidx));
+       GINAC_ASSERT(is_ex_of_type(i.op(2), spinidx));
+
+       const spinidx & i1 = ex_to_spinidx(i.op(1));
+       const spinidx & i2 = ex_to_spinidx(i.op(2));
+
+       // Convolutions are zero
+       if (static_cast<const indexed &>(i).get_dummy_indices().size() != 0)
+               return _ex0();
+
+       // Numeric evaluation
+       if (static_cast<const indexed &>(i).all_index_values_are(info_flags::nonnegint)) {
+               int n1 = ex_to_numeric(i1.get_value()).to_int(), n2 = ex_to_numeric(i2.get_value()).to_int();
+               if (n1 == n2)
+                       return _ex0();
+               else if (n1 < n2)
+                       return _ex1();
+               else
+                       return _ex_1();
+       }
+
+       // No further simplifications
+       return i.hold();
+}
+

 /** Automatic symbolic evaluation of an indexed epsilon tensor. */
 ex tensepsilon::eval_indexed(const basic & i) const
 {
 /** Automatic symbolic evaluation of an indexed epsilon tensor. */
 ex tensepsilon::eval_indexed(const basic & i) const
 {


@@ -385,7 +378,7 @@ 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 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
                return false;
 
        // Try to contract first index


@@ -420,6 +413,85 @@ again:
        return false;
 }
 
        return false;
 }
 

+/** Contraction of an indexed spinor metric with something else. */
+bool spinmetric::contract_with(exvector::iterator self, exvector::iterator other, exvector & v) const
+{
+       GINAC_ASSERT(is_ex_of_type(*self, indexed));
+       GINAC_ASSERT(is_ex_of_type(*other, indexed));
+       GINAC_ASSERT(self->nops() == 3);
+       GINAC_ASSERT(is_ex_of_type(self->op(0), spinmetric));
+
+       // Contractions between spinor metrics
+       if (is_ex_of_type(other->op(0), spinmetric)) {
+               const idx &self_i1 = ex_to_idx(self->op(1));
+               const idx &self_i2 = ex_to_idx(self->op(2));
+               const idx &other_i1 = ex_to_idx(other->op(1));
+               const idx &other_i2 = ex_to_idx(other->op(2));
+
+               if (is_dummy_pair(self_i1, other_i1)) {
+                       if (is_dummy_pair(self_i2, other_i2))
+                               *self = _ex2();
+                       else
+                               *self = delta_tensor(self_i2, other_i2);
+                       *other = _ex1();
+                       return true;
+               } else if (is_dummy_pair(self_i1, other_i2)) {
+                       if (is_dummy_pair(self_i2, other_i1))
+                               *self = _ex_2();
+                       else
+                               *self = -delta_tensor(self_i2, other_i1);
+                       *other = _ex1();
+                       return true;
+               } else if (is_dummy_pair(self_i2, other_i1)) {
+                       *self = -delta_tensor(self_i1, other_i2);
+                       *other = _ex1();
+                       return true;
+               } else if (is_dummy_pair(self_i2, other_i2)) {
+                       *self = delta_tensor(self_i1, other_i1);
+                       *other = _ex1();
+                       return true;
+               }
+       }
+
+       // If contracting with the delta tensor, let the delta do it
+       // (don't raise/lower delta indices)
+       if (is_ex_of_type(other->op(0), tensdelta))
+               return false;
+
+       // Try to contract first index
+       const idx *self_idx = &ex_to_idx(self->op(1));
+       const idx *free_idx = &ex_to_idx(self->op(2));
+       bool first_index_tried = false;
+       int sign = 1;
+
+again:
+       if (self_idx->is_symbolic()) {
+               for (int i=1; i<other->nops(); i++) {
+                       const idx &other_idx = ex_to_idx(other->op(i));
+                       if (is_dummy_pair(*self_idx, other_idx)) {
+
+                               // Contraction found, remove metric tensor and substitute
+                               // index in second object
+                               *self = (static_cast<const spinidx *>(self_idx)->is_covariant() ? sign : -sign);
+                               *other = other->subs(other_idx == *free_idx);
+                               return true;
+                       }
+               }
+       }
+
+       if (!first_index_tried) {
+
+               // No contraction with first index found, try second index
+               self_idx = &ex_to_idx(self->op(2));
+               free_idx = &ex_to_idx(self->op(1));
+               first_index_tried = true;
+               sign = -sign;
+               goto again;
+       }
+
+       return false;
+}
+

 //////////
 // global functions
 //////////
 //////////
 // global functions
 //////////


@@ -448,6 +520,16 @@ ex lorentz_g(const ex & i1, const ex & i2, bool pos_sig)
        return indexed(minkmetric(pos_sig), indexed::symmetric, i1, i2);
 }
 
        return indexed(minkmetric(pos_sig), indexed::symmetric, i1, i2);
 }
 

+ex spinor_metric(const ex & i1, const ex & i2)
+{
+       if (!is_ex_of_type(i1, spinidx) || !is_ex_of_type(i2, spinidx))
+               throw(std::invalid_argument("indices of spinor metric must be of type spinidx"));
+       if (!ex_to_idx(i1).get_dim().is_equal(2) || !ex_to_idx(i2).get_dim().is_equal(2))
+               throw(std::runtime_error("index dimension for spinor metric must be 2"));
+
+       return indexed(spinmetric(), indexed::antisymmetric, i1, i2);
+}
+

 ex epsilon_tensor(const ex & i1, const ex & i2)
 {
        if (!is_ex_of_type(i1, idx) || !is_ex_of_type(i2, idx))
 ex epsilon_tensor(const ex & i1, const ex & i2)
 {
        if (!is_ex_of_type(i1, idx) || !is_ex_of_type(i2, idx))


@@ -490,4 +572,16 @@ 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);
 }
 
        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
 } // namespace GiNaC