Version:

Last Modified: March 31, 2017

Continuously filters an input sequence using a specific filter.

A Boolean that specifies the initialization of the internal state of the node.

True | Initializes the internal state to zero. |

False | Initializes the internal state to the final state from the previous call of this node. |

This node automatically initializes the internal state to zero on the first call and runs continuously until this input is True.

**Default: **False

The input filter.

Structure of the filter.

Name | Value | Description |
---|---|---|

IIR Cascade 2nd Order | 0 | Uses IIR second-order filter stages. |

IIR Cascade 4th Order | 1 | Uses IIR fourth-order filter stages. |

IIR Direct | 2 | Uses the direct-form IIR filter. |

FIR | 3 | Uses the FIR filter. |

**Default: **IIR Cascade 2nd Order

Forward coefficients of the filter.

**Default: **0

Reverse coefficients of the filter.

**Default: **0

The sampling frequency in Hz.

This value must be greater than zero.

**Default: **0

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.

**Default: **No error

Error information.

The node produces this output according to standard error behavior.

Standard Error Behavior

**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.

If **filter structure** is FIR, this node obtains the elements of **filtered signal** using the following equation:

${y}_{i}=\begin{array}{cc}\underset{j=0}{\overset{{N}_{b}-1}{\sum}}{b}_{j}{x}_{i-j}& \mathrm{for}(i\ge 0)\end{array}$

where

*y*is**filtered signal***N*_{b}is the number of FIR coefficients*b*_{j}is the filter coefficients

If **filter structure** is IIR Direct, this node obtains the elements of **filtered signal** using the following equation:

${y}_{i}=\begin{array}{cc}\frac{1}{{a}_{0}}\left(\underset{j=0}{\overset{{N}_{b}-1}{\sum}}{b}_{j}{x}_{i-j}-\underset{k=1}{\overset{{N}_{a}-1}{\sum}}{a}_{k}{y}_{i-k}\right)& \mathrm{for}(i\ge 0)\end{array}$

where

*y*is**filtered signal***N*_{b}is the number of**forward coefficients***b*_{j}is the**forward coefficients***N*_{a}is the number of**reverse coefficients***a*_{k}is the**reverse coefficients**

If **filter structure** is IIR Cascade 2nd Order or IIR Cascade 4th Order, this node obtains the elements of **filtered signal** with a cascade of second- or fourth-order filter stages. The output of one filter stage is the input to the next filter stage for all *N*_{s} filter stages.

**Where This Node Can Run: **

Desktop OS: Windows

FPGA: This product does not support FPGA devices