Trace

The trace of a matrix is very easy to compute, but it helps to have its value, as it has special properties. It is defined as the sum of the values on the main diagonal of a matrix. So, let's say we have the following:

The trace of A will then be the following:

In general, the definition of the trace for an n × n square matrix is as follows:

The trace of a linear operator is the same for any matrix that represents it.