Talk:Shift-invariant system

Causality

"Because digital systems need not be causal, some operations can be implemented in the digital domain that cannot be implemented using discrete analog components". This is completely wrong. You cannot get revenues from horse races using digital systems. Digital (numerical) system are causal as any other: they can perform anticausal transformations only on a recording of a signal, e.c. acting on a file or on a buffer, which is in principle and actually possible also for analog systems, of course. Because such a procedure does not violate causality, being not realizable in real time.

--95.238.26.82 (talk) 10:14, 17 February 2013 (UTC)