def add_new_task(self, new_length):
        """Adds a new dimension to the accuracy matrix.

        :param new_length: The new dimension of the matrix. We assume a square
                            matrix
        """
        temp = self.matrix.clone()
        self.matrix = torch.zeros((new_length, new_length))
        self.matrix[: temp.size(0), : temp.size(1)] = temp
Adds a new dimension to the accuracy matrix.

        :param new_length: The new dimension of the matrix. We assume a square
                            matrix
        
avalanche/evaluation/metrics/acc_matrix.py