rffti#
Purpose#
Computes inverse real 1- or 2-D Fast Fourier transform.
Format#
- y = rffti(x)#
- Parameters:
x (NxK matrix) – data
- Returns:
y (LxM real matrix) – where \(L\) and \(M\) are the smallest prime factor products greater than or equal to \(N\) and \(K\).
Remarks#
It is up to the user to guarantee that the input will return a real result. If in doubt, use ffti().
Examples#
// Create an 8-element signal
x = { 1, 2, 3, 4, 5, 6, 7, 8 };
// Forward FFT
y = rfft(x);
// Inverse FFT recovers the original signal
z = rffti(y);
print "Original x:";
print x;
print "Recovered via rffti:";
print z;
The above code produces the following output:
Original x:
1.0000000
2.0000000
3.0000000
4.0000000
5.0000000
6.0000000
7.0000000
8.0000000
Recovered via rffti:
1.0000000
2.0000000
3.0000000
4.0000000
5.0000000
6.0000000
7.0000000
8.0000000