IIR filter response not infinite

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I just simulated the impulse response in matlab for a first order IIR low pass filter using the command impulse (tf[50],[1 50]). The output seems to be lasting for a finite period. Can anybody clarify?
 

It will asymptotically approach a final value. In real life with finite resolution it will eventually end.
 

Hi,

A digital system has limited resolution. As long as the variations are within +/-0.5 LSB around the current value you will see no change.
What else do you expect?

Btw: Similar with an analog system ... the limit here is "noise".

Klaus
 

tf([50],[1 50]) is a time continuous transfer function, not a time discrete IIR.
 

Hi FvM

Thanks for pointing it out. It was a typo. It was actually impulse of (c2d(continuous function)). Just to know more, how far will the response last. In matlab, there isn't any resolution issues.
 

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