symbolic 2x2 block matrix inversion
Is it possible in SAGE to get the 2x2 block matrix inversion described in Wikipedia?
A = matrix(SR, 2, 2, 'a1 a2 a3 a4'.split(' ')) B = matrix(SR, 2, 2, 'b1 b2 b3 b4'.split(' ')) C = matrix(SR, 2, 2, 'c1 c2 c3 c4'.split(' ')) D = matrix(SR, 2, 2, 'd1 d2 d3 d4'.split(' ')) M = block_matrix(SR, 2, 2, [A, B, C, D]) Mi = M.inverse() Mi.simplify_rational()
But it doesn't seem to be able to exactly reproduce the Wikipedia formula (it returns a horrible formula full of a1, a2, etc). Any idea?