//==================================================================
// signal = x, response = X
void Filter::fourierTransform (ComplexVector& signal, ComplexVector& response)
{
float N = response.size();
for (int k = 0; k < response.size(); ++k)
{
response[k] = newComplex(0, 0);
for (int n = 0; n < signal.size(); ++n)
{
float alpha = 2*M_PI * k / N * -n;
Complex Z = newComplex(cosf(alpha), sinf(alpha));
response[k] = response[k] + (signal[n] * Z);
}
response[k] = carToPol(response[k]);
}
}
int main(int argc, const char * argv[]) {
double rho = 0; //initialisation des var
double theta = 0;
double *prho = ρ
double *ptheta = θ
double x = 0;
double *px = &x;
double y = 0;
double *py = &y;
int menuChoice = 0;
void carToPol(double x,double y,double *prho,double *ptheta); //init des fonctions de pointeurs
void polToCar(double rho,double theta, double *px,double *py);
printf("Please choose :\n");
printf("1 - Cartesian to polar ? \n2 - Polar to Cartesian ?\n");
scanf("%d", &menuChoice);
switch (menuChoice) {
case 1:
printf("\nPlease input x : ");
scanf("%lf", &x);
printf("\nPlease input y : \n");
scanf("%lf", &y);
carToPol(x, y, prho, ptheta);
printf("Rho : %f \nTheta : %f\n", rho, theta);
break;
case 2:
printf("\nPlease input Rho : ");
scanf("%lf", &rho);
printf("\nPlease input Theta : \n");
scanf("%lf", &theta);
polToCar(rho, theta, px, py);
printf("x : %f \ny : %f \n",x,y);
break;
default:
printf("\nYou didn't choose either 1 or 2 !!!\nPlease try again !");
break;
}
}
float* Filter::getFrequencyResponse (int responseSize)
{
float* response = new float[responseSize];
for (int k = 0; k < responseSize; ++k)
{
Complex Y = newComplex(0, 0);
Complex X = newComplex(0, 0);
for (int n = 0; n < zeroBuffer.size; ++n)
{
float alpha = (float)k / responseSize * M_PI * -n;
Complex Z = newComplex(cosf(alpha), sinf(alpha));
Complex a = newComplex(zeroBuffer.coefficients[n], 0);
Y = Y + a * Z;
}
for (int n = 0; n < poleBuffer.size; ++n)
{
float alpha = (float)k / responseSize * M_PI * -n;
Complex Z = newComplex(cosf(alpha), sinf(alpha));
Complex b = newComplex(poleBuffer.coefficients[n], 0);
X = X - b * Z;
}
Complex H = Y / X;
float magnitude = carToPol(H).real;
response[k] = 20.0f * log10f(magnitude);
}
return response;
}