function FFTFromReal(const Vec: TMtxVec; VecIndex: Integer; Index: Integer; Len: Integer): TMtxVec;
The forward Fast Fourier Transformation (FFT) from real to complex.
| # | Name | Type | Description |
|---|---|---|---|
| 1 | Vec | TMtxVec | |
| 2 | VecIndex | Integer | |
| 3 | Index | Integer | start index |
| 4 | Len | Integer | element count |
Result: stored in self (calling object), returns self for chaining
Remarks:
Calculate the 1D FFT from real Vec elements [VecIndex]..[VecIndex+Len-1] and store the results in the calling object elements [Index]..[Index+Len-1]. The Len parameter must not be a power of two. Size and Matrix.Complex properties of the calling object must be set explicitly. An exception is raised if Matrix.ConditionCheck is True and Vec is not complex or if array borders are overrun.
This is the indexed version of the FFT routine Matrix.FFTFromReal. Look there for more information on FFT parameters and storage requirements.
See Also: Vector.IFFT, Matrix.IFFT1D