# FHT

Advanced Analysis Library Only

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

## Purpose

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

where | Xk is the kth point of the FHT
| and cas(k) = cos(k) + sin(k)

FHT can perform the operation in place and overwrite the input array.

### Example

/* Generate an array with random numbers and calculate its Fast Hartley Transform. */
double x[256];
n;
n = 256;
Uniform (n, 17, x);
FHT (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 values used to compute the FHT. On output, the Fast Hartley Transform. 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.