However, in the remainder of this article we will consider only square matrices.
When the blocks are square matrices of the same order further formulas hold.
Let be a square matrix whose columns are those eigenvectors, in any order.
The entries a form the main diagonal of a square matrix.
Any two square matrices of the same order can be added and multiplied.
Thus for example only a square matrix can be idempotent.
The case of a square invertible matrix also holds interest.
It is required to solve The square matrix has been used in Example 2.3.2.1.
The determinant takes a square matrix and returns a number.
This example shows that the Jacobian need not be a square matrix.