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#include "fftease.h"
void unconvert( float *C, float *S, int N2, float *lastphase, float fundamental, float factor )
{
int i,
real,
imag,
amp,
freq;
float mag,
phase;
double sin(), cos();
for ( i = 0; i <= N2; i++ ) {
imag = freq = ( real = amp = i<<1 ) + 1;
if ( i == N2 )
real = 1;
mag = C[amp];
lastphase[i] += C[freq] - i*fundamental;
phase = lastphase[i]*factor;
S[real] = mag*cos( phase );
if ( i != N2 )
S[imag] = -mag*sin( phase );
}
}
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