/********************************************************/
/*?WARNING:												*/
/*?This?code?cannot?be?used?in?any?aplication			*/
/*?without?permition?of?the?author						*/
/*?for?more?information?please?read?the?license?in?the	*/
/*?Numerical?Recipies?in?C?book?or?go?to?www.nr.com		*/
/*?this?is?mearly?an?example?of?how?to?use?it			*/
/********************************************************/


#include?“StdAfx.h“
#include?
#include?“.\fourier.h“

#define?SWAP（ab）?tempr=（a）;（a）=（b）;（b）=tempr

CFourier::CFourier（void）
{
	pi=4*atan（（double）1）;vector=NULL;
}

CFourier::~CFourier（void）
{if（vector!=NULL）
		delete?[]?vector;
}

//?FFT?1D

void?CFourier::ComplexFFT（float?data[]?unsigned?long?number_of_samples?unsigned?int?sample_rate?int?sign）
{

	//variables?for?the?fft
	unsigned?long?nmmaxmjistepi;
	double?wtempwrwprwpiwithetatemprtempi;

	//the?complex?array?is?real+complex?so?the?array?
????//as?a?size?n?=?2*?number?of?complex?samples
????//real?part?is?the?data[index]?and?
????//the?complex?part?is?the?data[index+1]

	//new?complex?array?of?size?n=2*sample_rate
	if（vector!=NULL）
????????delete?[]?vector;

	vector=new?float?[2*sample_rate];

	//put?the?real?array?in?a?complex?array
	//the?complex?part?is?filled?with?0‘s
	//the?remaining?vector?with?no?data?is?filled?with?0‘s
	for（n=0;?n	{
		if（n			vector[2*n]=data[n];
		else
			vector[2*n]=0;
		vector[2*n+1]=0;
	}

	//binary?inversion?（note?that?the?indexes?
????//start?from?0?witch?means?that?the
????//real?part?of?the?complex?is?on?the?even-indexes?
????//and?the?complex?part?is?on?the?odd-indexes）
	n=sample_rate?<	j=0;
	for?（i=0;i		if?（j?>?i）?{
			SWAP（vector[j]vector[i]）;
			SWAP（vector[j+1]vector[i+1]）;
			if（（j/2）<（n/4））{
				SWAP（vector[（n-（i+2））]vector[（n-（j+2））]）;
				SWAP（vector[（n-（i+2））+1]vector[（n-（j+2））+1]）;
			}
		}
		m=n?>>?1;
		while?（m?>=?2?&&?j?>=?m）?{
			j?-=?m;
			m?>>=?1;
		}
		j?+=?m;
	}
	//end?of?the?bit-reversed?order?algorithm

	//Danielson-Lanzcos?routine
	mmax=2;
	//external?loop
	while?（n?>?mmax）
	{
		istep=mmax?<		theta=sign*（2*pi/mmax）;
		wtemp=sin（0.5*theta）;
		wpr?=?-2.0*wtemp*wtemp;
		wpi=sin（theta）;
		wr=1.0;
		wi=0.0;
		//internal?loops
		for?（m=1;m			for?（i=m;i<=n;i+=istep）?{
				j=i+mmax;
				tempr=wr*vector[j-1]-wi*vector[j];
				tempi=wr*vector[j]+wi*vector[j-1];
				vector[j-1]=vector[i-1]-tempr;
				vector[j]=vector[i]-tempi;
				vector[i-1]?+=?tempr;
				vector[i]?+=?tempi;
			}
			wr=（wtemp=wr）*wpr-wi*wpi+wr;
			wi=wi*wpr+wtemp*wpi+wi;
		}
		mmax=istep;
	}
	//end?of?the?algorithm
	
	//determine?the?fundamental?frequency
	//look?for?the?maximum?absolute?value?in?the?complex?array
	fundamental_frequency=0;
	for（i=2;?i<=sample_rate;?i+=2）
	{
		if（（pow（vector[i]2）+pow（vector[i+1]2））>（pow（vector[fundamental_frequency]2）+pow（vector[fund

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件???????3277??2008-10-07?20:42??FFT_RecordHWnd\Fourier.cpp

?????文件????????401??2008-10-04?19:50??FFT_RecordHWnd\Fourier.h

?????文件???????3651??2003-10-19?17:09??FFT_RecordHWnd\ReadMe.txt

?????文件??????36956??2008-10-05?17:44??FFT_RecordHWnd\RecordHWnd.aps

?????文件???????1623??2008-10-08?16:30??FFT_RecordHWnd\RecordHWnd.clw

?????文件???????2119??2007-04-15?16:54??FFT_RecordHWnd\RecordHWnd.cpp

?????文件???????4434??2008-10-03?22:18??FFT_RecordHWnd\RecordHWnd.dsp

?????文件????????545??2007-04-15?16:06??FFT_RecordHWnd\RecordHWnd.dsw

?????文件???????1368??2003-10-19?17:09??FFT_RecordHWnd\RecordHWnd.h

?????文件?????132096??2008-10-08?16:30??FFT_RecordHWnd\RecordHWnd.ncb

?????文件?????126976??2008-10-08?16:30??FFT_RecordHWnd\RecordHWnd.opt

?????文件???????1366??2008-10-08?16:28??FFT_RecordHWnd\RecordHWnd.plg

?????文件???????6556??2008-10-05?17:44??FFT_RecordHWnd\RecordHWnd.rc

?????文件????????909??2008-05-30?10:36??FFT_RecordHWnd\RecordHWnd.sln

????..A..H.?????13312??2008-10-06?20:49??FFT_RecordHWnd\RecordHWnd.suo

?????文件???????6869??2008-05-30?10:36??FFT_RecordHWnd\RecordHWnd.vcproj

?????文件??????16011??2008-10-08?16:28??FFT_RecordHWnd\RecordHWndDlg.cpp

?????文件???????2735??2008-10-08?16:26??FFT_RecordHWnd\RecordHWndDlg.h

?????文件???????1078??2003-10-19?17:09??FFT_RecordHWnd\res\RecordHWnd.ico

?????文件????????402??2003-10-19?17:09??FFT_RecordHWnd\res\RecordHWnd.rc2

?????文件???????1193??2008-10-05?17:44??FFT_RecordHWnd\resource.h

?????文件???????2876??2008-05-05?14:47??FFT_RecordHWnd\SpectrumGraph.h

?????文件????????212??2003-10-19?17:09??FFT_RecordHWnd\StdAfx.cpp

?????文件???????1077??2008-10-07?13:08??FFT_RecordHWnd\StdAfx.h

?????目錄??????????0??2008-10-06?20:48??FFT_RecordHWnd\res

?????目錄??????????0??2008-10-08?16:30??FFT_RecordHWnd

-----------?---------??----------?-----??----

???????????????368042????????????????????26