Computes the backward FFT of each row in arrayinout and returns the complex conjugate symmetric results in-place
in a packed format. Use a DoubleSymmetricSignalReader instance to extract individual signal FFT's out of the resultant array.
Thrown when the signal data (each row) is shorter than this DoubleSymmetricBackward1DFFT instance.
Remarks
This is faster than computing each FFT one row at a time using a signal vector if signals are all of the same length.
Replaces deprecated FFTInPlace(double[,] arrayinout).