# Measures of Spread (Moment about Mean) (G Dataflow)

Last Modified: January 12, 2018

Computes the moment about the mean of a sequence using a specific order.  ## reset

A Boolean that specifies whether to reset the internal state of the node.

 True Resets the internal state of the node. False Does not reset the internal state of the node.

This input is available only if you wire a double-precision, floating-point number to x.

Default: False ## x

The input sequence.

If x is empty, moment is NaN.

This input accepts a double-precision, floating-point number or a 1D array of double-precision, floating-point numbers. ## order

Order of the calculated moment about mean.

order must be greater than 0. If order is less than or equal to 0, the node sets moment to NaN and returns an error.

Default: 2 ## sample length

Length of each set of data.

The node performs computation for each set of data. sample length must be greater than zero.

This input is available only if you wire a double-precision floating-point number to x.

Default: 100 ## error in

Error conditions that occur before this node runs.

The node responds to this input according to standard error behavior.

Standard Error Behavior

Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

error in does not contain an error error in contains an error  If no error occurred before the node runs, the node begins execution normally.

If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.

If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

Default: No error ## moment

Moment about the mean of the input sequence calculated using the specified order. ## error out

Error information.

The node produces this output according to standard error behavior.

Standard Error Behavior

Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

error in does not contain an error error in contains an error  If no error occurred before the node runs, the node begins execution normally.

If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.

If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

## Algorithm for Computing the Moment about the Mean of a Sequence

The node computes the mth-order moment using the following equation.

${\sigma }_{x}^{m}=\frac{1}{n}\underset{i=0}{\overset{n-1}{\sum }}{\left({x}_{i}-\mu \right)}^{m}$

where ${\sigma }_{x}^{m}$ is the mth-order moment, and n is the number of elements in the input sequence x.

Where This Node Can Run:

Desktop OS: Windows

FPGA: Not supported

Web Server: Not supported in VIs that run in a web application