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# reflect

Class: LagOp

Reflect lag operator polynomial coefficients around lag zero

B = reflect(A)

## Description

Given a lag operator polynomial object A(L),B = reflect(A) negates all coefficient matrices except the coefficient matrix at lag 0. For example, given a polynomial of degree p,

$A\left(L\right)=A0+A1×L+A2×{L}^{2}+...+AP×{L}^{p}$

the reflected polynomial B(L) is

$B\left(L\right)=A0-A1×L-A2×{L}^{2}-...-AP×{L}^{p}$

with the same degree and dimension as A(L).

## Examples

expand all

### Reflect a Lag Operator Polynomial

Create a LagOp polynomial and its reflection:

```A = LagOp({0.8 1 0 .6});
B = reflect(A)
```
```B =

1-D Lag Operator Polynomial:
-----------------------------
Coefficients: [0.8 -1 -0.6]
Lags: [0 1 3]
Degree: 3
Dimension: 1
```
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