Use kron to build a matrix

Hi,

I would like to build a matrix that resembles something like

A =   [-1   1       0       0       0       0       0       0;
       0   -1       1       0       0       0       0       0; 
       0    0       -1      1       0       0       0       0;
       0    0       0       -1      1       0       0       0;
       0    0       0       0       -1      1       0       0;
       0    0       0       0       0       -1      1       0;
       0    0       0       0       0       0       -1      1];

Can I use kron function to build something like this? One of the things that needs to be a variable will be the number of rows, so I need my kron function to be flexible such that it can build more such matrices, for eg. a matrix with four such rows would look like

A =   [-1   1       0       0       0;
       0   -1       1       0       0;
       0    0       -1      1       0;
       0    0       0       -1      1;]

Also happy to do using any other method than kron. Thank you for your help.

Answer 1

[Matt J]

No, the matrix you've shown is not a Kronecker product, but the matrix is easily generated using diff, e.g.,

A=full(diff(speye(7)))

A = 6×7

-1 1 0 0 0 0 0 0 -1 1 0 0 0 0 0 0 -1 1 0 0 0 0 0 0 -1 1 0 0 0 0 0 0 -1 1 0 0 0 0 0 0 -1 1

[Jyoti Mangal]

Thank you so much! This worked like a charm

[Stephen23]

A = diff(eye(7)) % no need for sparse array

A = 6×7

-1 1 0 0 0 0 0 0 -1 1 0 0 0 0 0 0 -1 1 0 0 0 0 0 0 -1 1 0 0 0 0 0 0 -1 1 0 0 0 0 0 0 -1 1

Answer 2

[Sulaymon Eshkabilov]

Hi,

In you exercise, use eye() and kron(). and then change the necessary element of the generated matrix if necessary.

Good luck