From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262111AbTJNJtO (ORCPT ); Tue, 14 Oct 2003 05:49:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262119AbTJNJs5 (ORCPT ); Tue, 14 Oct 2003 05:48:57 -0400 Received: from mail.jlokier.co.uk ([81.29.64.88]:45455 "EHLO mail.shareable.org") by vger.kernel.org with ESMTP id S262111AbTJNJsI (ORCPT ); Tue, 14 Oct 2003 05:48:08 -0400 Date: Tue, 14 Oct 2003 10:46:55 +0100 From: Jamie Lokier To: Piet Delaney Cc: George Anzinger , Clayton Weaver , linux-kernel@vger.kernel.org Subject: Re: Circular Convolution scheduler Message-ID: <20031014094655.GC24812@mail.shareable.org> References: <20031006161733.24441.qmail@email.com> <3F833C06.7000802@mvista.com> <1066120643.25020.121.camel@www.piet.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1066120643.25020.121.camel@www.piet.net> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Piet Delaney wrote: > circular convolution is used with the Fast Fourier Transform. > The frequency data goes from -N/2 ...0 ,,,, +N/2, > multiplying in the frequency domain is the same as > convolving in the time or space domain. The result of multiplying > a time series by say a filter is the same as convolving it > with the FFT of the filter. Both domains wrap around with the > FFT, so the normal convolution associated with the Fourier > transform is replace with the circular convolution. > > Many prediction algorithms are based on digital signal processing. > The Kalman filter for example was used by Harvey for forecasting > financial markets. The kernel likely has lots of time series that > could be used for system identification for predicting how to best > use system resources. Ok, but what is "circular convolution scheduling"? -- Jamie