fact: Definition diameter2 xi (H_xi: Is_refining_T xi) x1 y1 x2 y2 (Hx1:-Qone<=x1/\x1<=Qone) (Hy1:-Qone<=y1/\y1<=Qone) (Hx2:-Qone<=x2/\x2<=Qone) (Hy2:-Qone<=y2/\y2<=Qone) := let xi_ll:= as_Tensor_Q xi x1 y1 in let xi_lr:= as_Tensor_Q xi x1 y2 in let xi_rl:= as_Tensor_Q xi x2 y1 in let xi_rr:= as_Tensor_Q xi x2 y2 in (Qmax4 xi_ll xi_lr xi_rl xi_rr) - (Qmin4 xi_ll xi_lr xi_rl xi_rr).
imports: Streams Streams_addenda Raxioms