X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=ginac%2Fpolynomial%2Fcollect_vargs.cpp;h=c4368fb2a5d2c1849f1b8d377ba5fddd3b8ecd7a;hp=6dc26f6d6bfba5cf55945eadc34f19af27f1013c;hb=6201dc3c6562e0b8c174129af382fd5745de048f;hpb=1602530f716ba1d425a0667b897182b99c374823;ds=sidebyside

diff --git a/ginac/polynomial/collect_vargs.cpp b/ginac/polynomial/collect_vargs.cpp
index 6dc26f6d..c4368fb2 100644
--- a/ginac/polynomial/collect_vargs.cpp
+++ b/ginac/polynomial/collect_vargs.cpp
@@ -3,7 +3,7 @@
  *  Utility functions. */
 
 /*
- *  GiNaC Copyright (C) 1999-2009 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2010 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
@@ -148,8 +148,14 @@ ex_collect_to_ex(const ex_collect_t& ec, const GiNaC::exvector& vars)
 		exvector tv;
 		tv.reserve(vars.size() + 1);
 		for (std::size_t j = 0; j < vars.size(); ++j) {
-			if (ec[i].first[j] != 0)
-				tv.push_back(power(vars[j], ec[i].first[j]));
+			const exp_vector_t& exp_vector(ec[i].first);
+
+			bug_on(exp_vector.size() != vars.size(),
+				"expected " << vars.size() << " variables, "
+				"expression has " << exp_vector.size() << " instead");
+
+			if (exp_vector[j] != 0)
+				tv.push_back(power(vars[j], exp_vector[j]));
 		}
 		tv.push_back(ec[i].second);
 		ex tmp = (new mul(tv))->setflag(status_flags::dynallocated);
@@ -171,6 +177,18 @@ ex lcoeff_wrt(ex e, const exvector& x)
 	return ec.rbegin()->second;
 }
 
+exp_vector_t degree_vector(ex e, const exvector& vars)
+{
+	e = e.expand();
+	exp_vector_t dvec(vars.size());
+	for (std::size_t i = vars.size(); i-- != 0; ) {
+		const int deg_i = e.degree(vars[i]);
+		e = e.coeff(vars[i], deg_i);
+		dvec[i] = deg_i;
+	}
+	return dvec;
+}
+
 cln::cl_I integer_lcoeff(const ex& e, const exvector& vars)
 {
 	ex_collect_t ec;