implementation of a matrix

Hello! I want to implement the following matrix:

where is a given vector of random indices

Can someone help me to implement that?

[madhan ravi]

Did you do anything for your homework?

[Franziska Bömann]

yes, I did, but I cannot understand how to implement matrices, thats why I'm always asking about matrices.

[madhan ravi]

Ok , can you upload what you have tried?

Answer 1

[Thiago Henrique Gomes Lobato]

This should do:

rng(42)
n = 3;
x = rand(n,1);
A = ones(n,n+1);
Differences = x-x';
for idx=2:n+1
   A(:,idx) = A(:,idx-1).*Differences(:,idx-1);
end
x
A

x =

    0.3745
    0.9507
    0.7320


A =

    1.0000         0         0         0
    1.0000    0.5762         0         0
    1.0000    0.3575   -0.0782         0

[madhan ravi]

It’s a homework :/

Answer 2

[Bruno Luong]

n = 3;
x = rand(n+1,1);

A = cumprod([ones(size(x)), (x-x(1:end-1).')], 2)

[madhan ravi]

But why though? It’s pretty obvious it’s a homework question? It’s not a homework solving contest XD.