Help/UGens/Filters/HPZ1.html

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  29 <p class="p1"><span class="s1"><b>HPZ1<span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span></b></span><b><span class="Apple-tab-span">      </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>two point difference filter</b></p>
  30 <p class="p2"><br></p>
  31 <p class="p3"><span class="s2"><b>Inherits from: </b><a href="../../Core/Object.html"><b>Object</b></a></span><span class="s3"><b> : </b><a href="../../Core/Kernel/AbstractFunction.html"><span class="s4"><b>AbstractFunction</b></span></a><b> : </b><a href="../UGen.html"><span class="s5"><b>UGen</b></span></a></span><span class="s5"><b> : </b><a href="../Filter.html"><span class="s6"><b>Filter</b></span></a><b> : </b><a href="LPZ1.html"><span class="s6"><b>LPZ1</b></span></a></span></p>
  32 <p class="p2"><br></p>
  33 <p class="p1"><b>HPZ1.ar(in, mul, add)</b></p>
  34 <p class="p1"><b>HPZ1.kr(in, mul, add)</b></p>
  35 <p class="p2"><br></p>
  36 <p class="p1">A special case fixed filter. Implements the formula:</p>
  37 <p class="p2"><br></p>
  38 <p class="p4">out(i) = 0.5 * (in(i) - in(i-1))</p>
  39 <p class="p2"><br></p>
  40 <p class="p1">which is a two point differentiator.</p>
  41 <p class="p2"><br></p>
  42 <p class="p1">See also: <a href="HPZ2.html"><span class="s6">HPZ2</span></a></p>
  43 <p class="p2"><br></p>
  44 <p class="p5">// Compare:</p>
  45 <p class="p2"><br></p>
  46 <p class="p6">{ <span class="s7">WhiteNoise</span>.ar(0.25) }.play;</p>
  47 <p class="p7"><br></p>
  48 <p class="p6">{ <span class="s7">HPZ1</span>.ar(<span class="s7">WhiteNoise</span>.ar(0.25)) }.play;</p>
  49 <p class="p7"><br></p>
  50 <p class="p5">// HPZ1 is useful to detect changes in a signal:</p>
  51 <p class="p5">// see also <a href="HPZ2.html"><span class="s6">HPZ2</span></a></p>
  52 <p class="p6">(</p>
  53 <p class="p6">{<span class="Apple-converted-space"> <span class="Apple-tab-span">      </span></span></p>
  54 <p class="p6"><span class="Apple-tab-span">     </span><span class="s7">var</span> changingSignal = <span class="s7">LFNoise0</span>.ar(1000);<span class="Apple-converted-space"> </span></p>
  55 <p class="p6"><span class="Apple-tab-span">     </span><span class="s7">var</span> hpz1 = <span class="s7">HPZ1</span>.ar(changingSignal);</p>
  56 <p class="p6"><span class="Apple-tab-span">     </span>[hpz1, hpz1 &gt; 0, hpz1.abs &gt; 0]<span class="Apple-converted-space"> </span></p>
  57 <p class="p6">}.plot</p>
  58 <p class="p6">);</p>
  59 <p class="p8"><br></p>
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