const varidx & i1 = ex_to<varidx>(i.op(1));
const varidx & i2 = ex_to<varidx>(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)));
+ }
+
// A metric tensor with one covariant and one contravariant index gets
// replaced by a delta tensor
if (i1.is_covariant() != i2.is_covariant())
{
if (!is_ex_of_type(i1, varidx) || !is_ex_of_type(i2, varidx))
throw(std::invalid_argument("indices of metric tensor must be of type varidx"));
- ex dim = ex_to<idx>(i1).get_dim();
- if (!dim.is_equal(ex_to<idx>(i2).get_dim()))
- throw(std::invalid_argument("all indices of metric tensor must have the same dimension"));
return indexed(tensmetric(), sy_symm(), i1, i2);
}
{
if (!is_ex_of_type(i1, varidx) || !is_ex_of_type(i2, varidx))
throw(std::invalid_argument("indices of metric tensor must be of type varidx"));
- ex dim = ex_to<idx>(i1).get_dim();
- if (!dim.is_equal(ex_to<idx>(i2).get_dim()))
- throw(std::invalid_argument("all indices of metric tensor must have the same dimension"));
return indexed(minkmetric(pos_sig), sy_symm(), i1, i2);
}