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Tidy up for ROLI
author Geogaddi\David <d.m.ronan@qmul.ac.uk>
date Tue, 17 May 2016 18:50:19 +0100
parents 636c989477e7
children
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--- a/Lib/fftw-3.2.1/doc/html/.svn/text-base/Cycle-Counters.html.svn-base	Wed May 04 11:02:59 2016 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
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-<html lang="en">
-<head>
-<title>Cycle Counters - FFTW 3.2.1</title>
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-
-<h3 class="section">9.3 Cycle Counters</h3>
-
-<p><a name="index-cycle-counter-373"></a>
-FFTW's planner actually executes and times different possible FFT
-algorithms in order to pick the fastest plan for a given n.  In
-order to do this in as short a time as possible, however, the timer must
-have a very high resolution, and to accomplish this we employ the
-hardware <dfn>cycle counters</dfn> that are available on most CPUs. 
-Currently, FFTW supports the cycle counters on x86, PowerPC/POWER, Alpha,
-UltraSPARC (SPARC v9), IA64, PA-RISC, and MIPS processors.
-
-   <p><a name="index-compiler-374"></a>Access to the cycle counters, unfortunately, is a compiler and/or
-operating-system dependent task, often requiring inline assembly
-language, and it may be that your compiler is not supported.  If you are
-<em>not</em> supported, FFTW will by default fall back on its estimator
-(effectively using <code>FFTW_ESTIMATE</code> for all plans). 
-<a name="index-FFTW_005fESTIMATE-375"></a>
-You can add support by editing the file <code>kernel/cycle.h</code>; normally,
-this will involve adapting one of the examples already present in order
-to use the inline-assembler syntax for your C compiler, and will only
-require a couple of lines of code.  Anyone adding support for a new
-system to <code>cycle.h</code> is encouraged to email us at <a href="mailto:fftw@fftw.org">fftw@fftw.org</a>.
-
-   <p>If a cycle counter is not available on your system (e.g. some embedded
-processor), and you don't want to use estimated plans, as a last resort
-you can use the <code>--with-slow-timer</code> option to <code>configure</code> (on
-Unix) or <code>#define WITH_SLOW_TIMER</code> in <code>config.h</code> (elsewhere). 
-This will use the much lower-resolution <code>gettimeofday</code> function, or even
-<code>clock</code> if the former is unavailable, and planning will be
-extremely slow.
-
-<!--  -->
-</body></html>
-