John wrote:
> Please help me find out if this is a special (square) matrix. > Every cell in the diagonal, the last row and the last column of the > matrix is not zero. So the matrix basically looks like an arrow pointing south-east. > All other cells are zero. > The matrix is not necessarily symmetric. > Is it a special matrix? Obviously, but I have not seen a name for it. > Any formula for the determinant? You can develop the determinant along the first column (or row), which leaves you with a matrix of the same type of dimension n-1 and a "check" matrix (nonzero pattern \|). Continuing recursively I find (though I am usually over-optimistic and my algebra is notoriously bad) that det A = [prod(a_ii)] * [ 1 - sum( (-1)^(n-i)a_ni/a_ii)]. . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
