MATLAB: How to do a lower triangular with ones along the diagonal

Question

Hello,

I want to do a lower triangular with ones along the diagonal. for example, I have 62 x 62 matrix of (binary of 1s and 0s) and wants to transfer this matrix to a lower triangular with ones along the diagonal

here, I use zeros for create A= 62 x 62 matrix and used tril(A) to get the lower triangular matrix

A=zeros(62,62);
tril(A);

I get a lower triangular matrix but how to get a lower triangular with ones along the diagonal from matrix A?

please, help me.

Thanks

Answer 1

Extracting the lower triangle from A and setting the main diagonal to 1:

tril(A,-1) + diag(ones(1,size(A,1))

Extracting the lower triangle from A and setting the first diagonal of the lower triangle to 1:

tril(A,-2) + diag(ones(1,size(A,1)-1),-1)