Hey guys, having a little trouble understanding whether or not a system is causal or not. I d'nt think this classifies as homework; at least I hope not.(adsbygoogle = window.adsbygoogle || []).push({});

Basically I'm confused as to how you would go about determining whether or not a system is causal.

For example, say any function x[n] = u[n];

So basically the signal is only active for n>=0;

y[n] = sin[n];

So you have an output for n<=0 when there is no signal propogating into the system. Thus I would assume that this system is non-causal, because the output is somehow anticipatory.

However, what if the output y[n] actually does depend on inputs of 0. So y[n] for n<=0 actually does result from x[n] = 0, wouldn't that make it causal then?

Not sure if this makes any sense whatsoever, hopefully someone can share some insight on this topic.

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# Determining Causal Systems

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