# Spectrum

Advanced Analysis Library Only

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

## Purpose

Calculates the power spectrum of the input array. Spectrum uses the following formula to obtain the power spectrum ps:

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

### Example

/* Generate an array with random numbers and calculate its power spectrum. */
double x[256];
int n;
n = 256;
Uniform (n, 17, x);
Spectrum (x, n);

## Parameters

Input
Name | Type | Description
numberOfElements | integer | Number of elements in the input array.
Output
Name | Type | Description
array | double-precision array | On input, the array used to compute the power spectrum. On output, the power spectrum. 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.