Non-recursive difference equation example: simple low-pass filter

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Noisy, discrete-time waveform 

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Filter #1

Time domain 
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Frequency domain 
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Filter frequency response 
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Filter #2

Time domain 
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Frequency domain 
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Filter frequency response 
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Filter #3

Time domain 
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Frequency domain 
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Filter frequency response 
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Pass through single frequency 
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Converted by Mathematica      January 17, 2003