## TransferFunctionFilter

The TransferFunctionFilter calculates the output for one-dimensional digital filters. Where the input, , is a ( x 1) vector of inputs and the output, , is a ( x 1) vector of outputs. The filter is described by vectors and and implemented using the standard difference equation:

If is not equal to 1, the coefficients are normalised by .

### ROS API

#### Parameters

`~name`(

`string`, default: Required)

- Name of the filter

`~type`(

`)`

`(`

`string`, default: Required)

- The filter's typename as declared in it's pluginlib registration:
`MultiChannelTransferFunctionFilterDouble`or`TransferFunctionFilterDouble`

`~params/a`(

`double`, default: Required)

- A vector of coefficients

`~params/b`(

`double`, default: Required)

- A vector of coefficients

**Example Configuration:**

LowPass: name: my_filter type: MultiChannelTransferFunctionFilterDouble params: a: [1.0, -0.509525449494429] b: [0.245237275252786, 0.245237275252786]