--- /dev/null
+/** @file exam_color.cpp
+ *
+ * Here we test GiNaC's color objects (su(3) Lie algebra). */
+
+/*
+ * GiNaC Copyright (C) 1999-2001 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
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include "exams.h"
+
+static unsigned check_equal(const ex &e1, const ex &e2)
+{
+ ex e = e1 - e2;
+ if (!e.is_zero()) {
+ clog << e1 << "-" << e2 << " erroneously returned "
+ << e << " instead of 0" << endl;
+ return 1;
+ }
+ return 0;
+}
+
+static unsigned check_equal_simplify(const ex &e1, const ex &e2)
+{
+ ex e = simplify_indexed(e1) - e2;
+ if (!e.is_zero()) {
+ clog << "simplify_indexed(" << e1 << ")-" << e2 << " erroneously returned "
+ << e << " instead of 0" << endl;
+ return 1;
+ }
+ return 0;
+}
+
+static unsigned color_check1(void)
+{
+ // checks general identities and contractions
+
+ unsigned result = 0;
+
+ idx a(symbol("a"), 8), b(symbol("b"), 8), c(symbol("c"), 8), d(symbol("d"), 8);
+
+ // structure constants
+ result += check_equal(color_d(a, c, a), 0);
+ result += check_equal_simplify(color_d(a, b, c) * color_d(b, d, c), numeric(5,3) * delta_tensor(a, d));
+ result += check_equal_simplify(color_d(idx(5, 8), b, c) * color_d(b, idx(5, 8), c), numeric(5,3));
+ result += check_equal_simplify(color_d(a, b, c) * color_d(b, c, a), numeric(40,3));
+ result += check_equal_simplify(color_d(a, b, c) * color_f(b, d, c), 0);
+ result += check_equal_simplify(color_d(a, b, c) * color_f(b, c, a), 0);
+ result += check_equal_simplify(color_f(a, b, c) * color_f(b, c, a), 24);
+ result += check_equal_simplify(color_f(a, b, c) * color_f(b, d, c), -3 * delta_tensor(a, d));
+ result += check_equal_simplify(color_h(a, b, c) * color_h(a, b, c), numeric(-32,3));
+ result += check_equal_simplify(color_h(a, b, c) * color_h(b, a, c), numeric(112,3));
+
+ ex e = color_h(a, b, c) * color_h(a, b, c);
+ ex sum = 0;
+ for (int i=1; i<9; i++)
+ for (int j=1; j<9; j++)
+ for (int k=1; k<9; k++)
+ sum += e.subs(lst(a == i, b == j, c == k));
+ if (!sum.is_equal(numeric(-32,3))) {
+ clog << "numeric contraction of " << e << " erroneously returned "
+ << sum << " instead of -32/3" << endl;
+ result++;
+ }
+
+ return result;
+}
+
+unsigned exam_color(void)
+{
+ unsigned result = 0;
+
+ cout << "examining color objects" << flush;
+ clog << "----------color objects:" << endl;
+
+ result += color_check1(); cout << '.' << flush;
+
+ if (!result) {
+ cout << " passed " << endl;
+ clog << "(no output)" << endl;
+ } else {
+ cout << " failed " << endl;
+ }
+
+ return result;
+}