From: Christian Bauer <Christian.Bauer@uni-mainz.de>
Date: Sat, 25 Jan 2003 00:29:20 +0000 (+0000)
Subject: delta tensor makes itself square
X-Git-Tag: release_1-1-0~37
X-Git-Url: https://ginac.de/ginac.git//ginac.git?a=commitdiff_plain;h=4e4f76e1b800566ec87058f466a6bbcaa2cfdc25;p=ginac.git

delta tensor makes itself square
---

diff --git a/ginac/tensor.cpp b/ginac/tensor.cpp
index f158ae65..1574bb66 100644
--- a/ginac/tensor.cpp
+++ b/ginac/tensor.cpp
@@ -180,6 +180,13 @@ ex tensdelta::eval_indexed(const basic & i) const
 	const idx & i1 = ex_to<idx>(i.op(1));
 	const idx & i2 = ex_to<idx>(i.op(2));
 
+	// The dimension of the indices must be equal, otherwise we use the minimal
+	// dimension
+	if (!i1.get_dim().is_equal(i2.get_dim())) {
+		ex min_dim = i1.minimal_dim(i2);
+		return i.subs(lst(i1 == i1.replace_dim(min_dim), i2 == i2.replace_dim(min_dim)));
+	}
+
 	// Trace of delta tensor is the (effective) dimension of the space
 	if (is_dummy_pair(i1, i2)) {
 		try {