filter (MathScript RT Module Function)
Owning Class: filter implementation
Requires: MathScript RT Module
Syntax
y = filter(b, a, x)
y = filter(b, a, x, 'direct')
[y, final] = filter(b, a, x, initial)
[y, final] = filter(b, a, x, initial, 'direct')
Description
Applies a one-dimensional filter. filter works for vectors and matrices only.
Inputs
| Name | Description |
|---|---|
| b | Specifies the forward filter coefficients. b is a vector. |
| a | Specifies the backward filter coefficients. If the first backward filter coefficient does not equal 1, LabVIEW normalizes the elements in a by the first backward filter coefficient. a is a vector. |
| x | Specifies the signal to filter. x is a real or complex vector. |
| initial | Specifies the initial conditions. initial is a vector. |
| 'direct' | Directs LabVIEW to use a direct convolution instead of a Fourier transform. Fourier transforms are faster for larger signals and filter lengths, but they introduce a small amount of round-off noise. |
Outputs
| Name | Description |
|---|---|
| y | Returns the filtered signal. y is a real or complex vector. |
| final | Returns the final conditions. final is a vector. |
Examples
x = 0:0.01:1;
b = [1];
a = [1, 1, 1];
y = filter(b, a, x)