What are built-in functions for handling matrices

Описание: We discuss matrix anatomy and built-in functions to refer to special structures in matrices:

00:00 -Introduction
00:10 -Definition of the main diagonal elements of a matrix
01:09 -Definition of the main diagonal (band) of a matrix
01:24 -Syntax: diag function to extract the diagonals of a matrix
01:52 -Example 1: Use diag to grab main diagonal band of 8x8 identity matrix
02:16 -Example 2: Use diag to grab main diagonal of gcd matrix
03:29 -Definition of the diagonal bands of a matrix
05:44 -Why are diagonal bands interesting?
05:58 -Example 4: The diag function to grab diagonal bands of a matrix
08:55 -Syntax: Use diag function to define diagonal matrices
09:19 -Example 5: Create 4x4 diagonal matrix with twos on main diagonal
09:43 -Example 6: Create 5x5 diagonal matrix with pre-determined diagonals
10:05 -Example 7: Populate diagonal bands of a matrix
10:37 -Example 8: Create a finite difference matrix using diag functions
11:43 -Definition of the lower triangular entries of a matrix
13:05 -Example 9: Use tril function to extract lower triangular entries
15:29 -Definition of the upper triangular entries of a matrix
15:57 -Syntax: triu function to extract upper triangular elements
16:13 -Example 10: Use triu function to extract upper triangular entries
16:51 -Syntax: reshape function documentation
17:31 -Conclusion