Open in new tab Notation . Meaning . a [...

Notation	Meaning
$a_{[i]}$	The ith element of vector a.
X	The set X.
$\bar{X}$	The complement of set X, includes all elements in a universal set not present in X.
$A_{[i]}$	The ith row of matrix A.
$A_{[*, i]}$	The ith column of matrix A.
$A_{[X]}$	Submatrix of matrix A containing only the rows present in set X.
$A_{[*, X]}$	Submatrix of matrix A containing all rows, but only the columns present in set X.
$[A B]$	A block matrix comprising of two smaller matrixes A and B stacked horizontally.
$[\begin{matrix} A \\ B \end{matrix}]$	A block matrix comprising of two smaller matrixes A and B stacked vertically.
$A ≻ 0$	Matrix A is positive-definite.

Notation	Meaning
$a_{[i]}$	The ith element of vector a.
X	The set X.
$\bar{X}$	The complement of set X, includes all elements in a universal set not present in X.
$A_{[i]}$	The ith row of matrix A.
$A_{[*, i]}$	The ith column of matrix A.
$A_{[X]}$	Submatrix of matrix A containing only the rows present in set X.
$A_{[*, X]}$	Submatrix of matrix A containing all rows, but only the columns present in set X.
$[A B]$	A block matrix comprising of two smaller matrixes A and B stacked horizontally.
$[\begin{matrix} A \\ B \end{matrix}]$	A block matrix comprising of two smaller matrixes A and B stacked vertically.
$A ≻ 0$	Matrix A is positive-definite.