From: Christian Bauer <Christian.Bauer@uni-mainz.de>
Date: Wed, 30 May 2001 22:38:28 +0000 (+0000)
Subject: - permutation_sign() and shaker_sort() are no longer inlined
X-Git-Tag: release_0-9-0~29
X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=commitdiff_plain;h=2700b3fa9c3a81236e8ceccb6aa9d5ea5848a1a0

- permutation_sign() and shaker_sort() are no longer inlined
- symmetrize() no longer limited to 32-bit integers
---

diff --git a/ginac/clifford.cpp b/ginac/clifford.cpp
index 3af4fcae..e62def50 100644
--- a/ginac/clifford.cpp
+++ b/ginac/clifford.cpp
@@ -524,7 +524,7 @@ ex canonicalize_clifford(const ex & e)
 			for (unsigned j=0; j<rhs.nops(); j++)
 				v.push_back(rhs.op(j));
 
-			// Stupid bubble sort because we only want to swap adjacent gammas
+			// Stupid recursive bubble sort because we only want to swap adjacent gammas
 			exvector::iterator it = v.begin(), next_to_last = v.end() - 1;
 			if (is_ex_of_type(it->op(0), diracgamma5))
 				it++;
diff --git a/ginac/inifcns.cpp b/ginac/inifcns.cpp
index beb51d62..03acbc7f 100644
--- a/ginac/inifcns.cpp
+++ b/ginac/inifcns.cpp
@@ -538,25 +538,18 @@ static ex symm(const ex & e, exvector::const_iterator first, exvector::const_ite
 	shaker_sort(iv_lst.begin(), iv_lst.end(), ex_is_less());
 	lst orig_lst(iv_lst);
 
-	// With n objects there are n! possible permutations
-	int num_perms = factorial(numeric(num)).to_int();
-
 	// Loop over all permutations (the first permutation, which is the
 	// identity, is unrolled)
 	ex sum = e;
-	int i = 1;
-	do {
-		next_permutation(iv_lst.begin(), iv_lst.end(), ex_is_less());
+	while (next_permutation(iv_lst.begin(), iv_lst.end(), ex_is_less())) {
 		ex term = e.subs(orig_lst, lst(iv_lst));
 		if (asymmetric) {
 			exlist test_lst = iv_lst;
 			term *= permutation_sign(test_lst.begin(), test_lst.end(), ex_is_less());
 		}
 		sum += term;
-		i++;
-	} while (i < num_perms);
-
-	return sum / num_perms;
+	}
+	return sum / factorial(numeric(num));
 }
 
 ex symmetrize(const ex & e, exvector::const_iterator first, exvector::const_iterator last)
diff --git a/ginac/utils.h b/ginac/utils.h
index c0bc2efe..ac7aecdf 100644
--- a/ginac/utils.h
+++ b/ginac/utils.h
@@ -131,7 +131,7 @@ inline unsigned golden_ratio_hash(unsigned n)
    explicitly supplied comparison function. If the sign returned is 1 or -1,
    the container is sorted after the operation. */
 template <class It>
-inline int permutation_sign(It first, It last)
+int permutation_sign(It first, It last)
 {
 	if (first == last)
 		return 0;
@@ -184,7 +184,7 @@ inline int permutation_sign(It first, It last)
 }
 
 template <class It, class Cmp>
-inline int permutation_sign(It first, It last, Cmp comp)
+int permutation_sign(It first, It last, Cmp comp)
 {
 	if (first == last)
 		return 0;
@@ -238,7 +238,7 @@ inline int permutation_sign(It first, It last, Cmp comp)
 
 /* Implementation of shaker sort, only compares adjacent elements. */
 template <class It, class Cmp>
-inline void shaker_sort(It first, It last, Cmp comp)
+void shaker_sort(It first, It last, Cmp comp)
 {
 	if (first == last)
 		return;