InvFHT

Advanced Analysis Library Only

AnalysisLibErrType InvFHT (double array[], int numberOfElements);

Purpose

Calculates the inverse Fast Hartley Transform (FHT) using the following formula:

where Xi is the point of the inverse FHT
and cas(x) = cos(x) + sin(x)

InvFHT performs the operation in place and overwrites the input array.

Example

/* Generate an array with random numbers and calculate its inverse Fast Hartley Transform. */
double x[256];
int n;
n = 256;
Uniform (n, 17, x);
InvFHT (x, n);

Parameters

Input
Name Type Description
numberOfElements integer Number of elements in the input array.

Default Value: 1024

Valid Values: Powers of 2.
Output
Name Type Description
array double-precision array On input, the array used to compute the inverse FHT.

On output, the inverse FHT.

This operation is performed in place, meaning the values in this array are overwritten.

Return Value

Name Type Description
status AnalysisLibErrType A value that specifies the type of error that occurred. Refer to analysis.h for definitions of these constants.