Transpose
Transpose
The transpose of a matrix is formed by flipping it over its diagonal — turning row i into column i.
If A is an m \times n matrix, then its transpose A^\top (or sometimes A^T) is an n \times m matrix.
A = \begin{bmatrix} 1 & 2 & 3 \\ 4 & 5 & 6 \end{bmatrix}
A^\top = \begin{bmatrix} 1 & 4 \\ 2 & 5 \\ 3 & 6 \end{bmatrix}
Transposes help define symmetry. A matrix A is symmetric if A = A^\top.