Metric
Makes a two-tensor a metric.
Labels the object as a symmetric tensor, and optionally gives it the
indicated signature through the signature parameter.g_{m n}::Metric(signature=1).
ex:= g_{m n} A^{n p};
eliminate_metric(_);
\(\displaystyle{}g_{m n} A^{n p}\)
{\color{red}{
Traceback (most recent call last): File "<string>", line 3, in <module> NameError: name 'eliminate_metric' is not defined}}
Objects declared as
Metric
can be used to automatically
raise or lower indices using the
eliminate_metric
algorithm, as above.