Running mean filtering using Window Functions? - Mailing list pgsql-sql
From | Andreas Gaab |
---|---|
Subject | Running mean filtering using Window Functions? |
Date | |
Msg-id | 48DA836F3865C54B8FBF424A3B775AF6674B452B86@Exchange-Server Whole thread Raw |
List | pgsql-sql |
<div class="WordSection1"><p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Times New Roman","serif"">Hi,</span><pclass="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Times New Roman","serif""> </span><pclass="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Times New Roman","serif"">canI realize a running mean filter using window functions?</span><p class="MsoNormal"><span lang="EN-US"style="font-size:11.0pt;font-family:"Times New Roman","serif""> </span><p class="MsoNormal"><span lang="EN-US"style="font-size:11.0pt;font-family:"Times New Roman","serif"">What I can think of is:</span><p class="MsoNormal"><spanlang="EN-US" style="font-size:11.0pt;font-family:"Times New Roman","serif""> </span><p class="MsoNormal"><spanlang="EN-US" style="font-size:11.0pt;font-family:"Times New Roman","serif"">SELECT avg(random) OVER(PARTITION BY floor(time_s / 60) ORDER BY floor(time_s / 60)) </span><p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"TimesNew Roman","serif"">FROM (</span><p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"TimesNew Roman","serif"">SELECT generate_series(0,600,20) time_s, random()</span><pclass="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Times New Roman","serif"">) asdata;</span><p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Times New Roman","serif""> </span><pclass="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Times New Roman","serif"">whichaverages all measurements in one minute, but not every line with its following two lines.</span><p class="MsoNormal"><spanlang="EN-US" style="font-size:11.0pt;font-family:"Times New Roman","serif""> </span><p class="MsoNormal"><spanlang="EN-US" style="font-size:11.0pt;font-family:"Times New Roman","serif"">Any suggestions?</span><pclass="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Times New Roman","serif""> </span><pclass="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Times New Roman","serif"">Bestregards</span><p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Times NewRoman","serif"">Andreas</span><p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Times New Roman","serif""> </span><pclass="MsoNormal"><span style="font-size:10.0pt">___________________________________________________________________________</span><p class="MsoNormal"><spanstyle="font-size:10.0pt"> </span><p class="MsoNormal"><span style="font-size:10.0pt">SCANLAB AG</span><pclass="MsoNormal"><span style="font-size:10.0pt">Dr. Andreas Simon Gaab</span><pclass="MsoNormal"><span style="font-size:10.0pt">Entwicklung • R & D</span><pclass="MsoNormal"><span style="font-size:10.0pt"> </span><p class="MsoNormal"><span style="font-size:10.0pt">Siemensstr. 2a• 82178 Puchheim • Germany</span><p class="MsoNormal"><span style="font-size:10.0pt">Tel. +49 (89) 800 746-513• Fax +49 (89) 800 746-199</span><p class="MsoNormal"><span style="font-size:10.0pt"><ahref="mailto:a.gaab@scanlab.de">mailto:a.gaab@scanlab.de</a> • <a href="http://www.scanlab.de">www.scanlab.de</a></span><pclass="MsoNormal"><span style="font-size:10.0pt"> </span><p class="MsoNormal"><spanstyle="font-size:10.0pt">Amtsgericht München: HRB 124707 • USt-IdNr.: DE 129 456 351</span><p class="MsoNormal"><spanstyle="font-size:10.0pt">Vorstand: Georg Hofner (Sprecher), Christian Huttenloher, Norbert Petschik</span><pclass="MsoNormal"><span style="font-size:10.0pt">Aufsichtsrat (Vorsitz): Dr. Hans J. Langer</span><pclass="MsoNormal"><span style="font-size:10.0pt">___________________________________________________________________________</span><span style="font-size:11.0pt;font-family:"Calibri","sans-serif""></span><pclass="MsoNormal"> </div>