👉 Dirac's delta function, named after Paul Dirac, is a mathematical function that represents an infinite impulse response (IIR) filter. It was introduced by mathematician and physicist John von Neumann in his 1927 paper "The Infinite IRR", which described the concept of a finite impulse response (FIR) filter. Dirac's delta function is also known as the unit impulse or Dirac delta function, but it should be noted that there is no direct connection between
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