documentation update

[ginac.git] / ginac / idx.cpp

diff --git a/ginac/idx.cpp b/ginac/idx.cpp
index be1d9483cb2d93d3c10afa7faad3081fa6aa5a25..63d29971bff122f3e34e40ba9a6eb866acbd7717 100644 (file)
--- a/ginac/idx.cpp
+++ b/ginac/idx.cpp
@@ -3,7 +3,7 @@
  *  Implementation of 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
@@ -20,12 +20,13 @@
  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
+#include <iostream>
 #include <stdexcept>
-#include <algorithm>
 
 #include "idx.h"
 #include "symbol.h"
 #include "lst.h"
+#include "relational.h"
 #include "print.h"
 #include "archive.h"
 #include "utils.h"
@@ -156,7 +157,9 @@ void idx::print(const print_context & c, unsigned level) const
 
        } else {
 
-               if (!is_of_type(c, print_latex))
+               if (is_a<print_latex>(c))
+                       c.s << "{";
+               else
                        c.s << ".";
                bool need_parens = !(is_ex_exactly_of_type(value, numeric) || is_ex_of_type(value, symbol));
                if (need_parens)
@@ -164,6 +167,8 @@ void idx::print(const print_context & c, unsigned level) const
                value.print(c);
                if (need_parens)
                        c.s << ")";
+               if (is_a<print_latex>(c))
+                       c.s << "}";
        }
 }
 
@@ -180,8 +185,9 @@ void varidx::print(const print_context & c, unsigned level) const
                dim.print(c, level + delta_indent);
 
        } else {
-
-               if (!is_of_type(c, print_latex)) {
+               if (is_a<print_latex>(c))
+                       c.s << "{";
+               else {
                        if (covariant)
                                c.s << ".";
                        else
@@ -193,6 +199,8 @@ void varidx::print(const print_context & c, unsigned level) const
                value.print(c);
                if (need_parens)
                        c.s << ")";
+               if (is_a<print_latex>(c))
+                       c.s << "}";
        }
 }
 
@@ -212,7 +220,12 @@ void spinidx::print(const print_context & c, unsigned level) const
        } else {
 
                bool is_tex = is_of_type(c, print_latex);
-               if (!is_tex) {
+               if (is_tex) {
+                       if (covariant)
+                               c.s << "_{";
+                       else
+                               c.s << "^{";
+               } else {
                        if (covariant)
                                c.s << ".";
                        else
@@ -232,6 +245,8 @@ void spinidx::print(const print_context & c, unsigned level) const
                        c.s << ")";
                if (is_tex && dotted)
                        c.s << "}";
+               if (is_tex)
+                       c.s << "}";
        }
 }
 
@@ -380,7 +395,8 @@ bool idx::is_dummy_pair_same_type(const basic & other) const
 {
        const idx &o = static_cast<const idx &>(other);
 
-       // Only pure symbols form dummy pairs, "2n+1" doesn't
+       // Only pure symbols form dummy pairs, numeric indices and expressions
+       // like "2n+1" don't
        if (!is_ex_of_type(value, symbol))
                return false;
 
@@ -388,8 +404,12 @@ bool idx::is_dummy_pair_same_type(const basic & other) const
        if (!value.is_equal(o.value))
                return false;
 
-       // Also the dimension
-       return dim.is_equal(o.dim);
+       // Dimensions need not be equal but must be comparable (so we can
+       // determine the minimum dimension of contractions)
+       if (dim.is_equal(o.dim))
+               return true;
+
+       return (dim < o.dim || dim > o.dim || (is_a<numeric>(dim) && is_a<symbol>(o.dim)) || (is_a<symbol>(dim) && is_a<numeric>(o.dim)));
 }
 
 bool varidx::is_dummy_pair_same_type(const basic & other) const
@@ -419,6 +439,24 @@ bool spinidx::is_dummy_pair_same_type(const basic & other) const
 // non-virtual functions
 //////////
 
+ex idx::replace_dim(const ex & new_dim) const
+{
+       idx *i_copy = static_cast<idx *>(duplicate());
+       i_copy->dim = new_dim;
+       i_copy->clearflag(status_flags::hash_calculated);
+       return i_copy->setflag(status_flags::dynallocated);
+}
+
+ex idx::minimal_dim(const idx & other) const
+{
+       if (dim.is_equal(other.dim) || dim < other.dim || (is_a<numeric>(dim) && is_a<symbol>(other.dim)))
+               return dim;
+       else if (dim > other.dim || (is_a<symbol>(dim) && is_a<numeric>(other.dim)))
+               return other.dim;
+       else
+               throw (std::runtime_error("idx::minimal_dim: index dimensions cannot be ordered"));
+}
+
 ex varidx::toggle_variance(void) const
 {
        varidx *i_copy = static_cast<varidx *>(duplicate());