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Computes the inverse fast Hartley transform (FHT) of the input sequence.

The number of elements in the real input sequence X must be a valid power of two.

Details  

	X is the input sequence. To properly compute the inverse FHT of X, the number of elements, n, in the sequence must be a valid power of 2. n = 2m where m = 1, 2, 3,…,10 If the number of elements in X is not a valid power of 2, the VI sets Inv FHT{X} to an empty array.
	Inv FHT {X} is the inverse Hartley transform of X.

Inverse FHT Details

The inverse Hartley transform of a function X(f) is defined as

,

where cas(x) = cos(x) + sin(x).

If Y represents the output sequence Inv FHT{X}, the Inverse FHT VI calculates Y through the discrete implementation of the inverse Hartley integral

for k = 1, 2, …n – 1,

where n is the number of elements in X.

The inverse Hartley transform maps real-valued frequency sequences into real-valued sequences. You can use it instead of the inverse Fourier transform to convolve, deconvolve, and correlate signals. You also can derive the Fourier transform from the Hartley transform.

Refer to the FHT VI for a comparison of the Fourier and Hartley transforms.