# lp2LS

Laurent polynomials to lifting steps and normalization factors

## Syntax

``[lsteps,k] = lp2LS(wavetype,LoRz,HiRz,factmode)``

## Description

example

````[lsteps,k] = lp2LS(wavetype,LoRz,HiRz,factmode)` returns the lifting scheme steps `lsteps` and normalization factors `k` associated with the Laurent polynomials `LoRz` and `HiRz`. `wavetype` specifies the wavelet type corresponding to the Laurent polynomials, and `factmode` specifies the factorization mode.```

## Examples

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Create a lifting scheme associated with the `db2` wavelet.

```wv = "db2"; lsw = liftingScheme(Wavelet=wv);```

Obtain the Laurent polynomials associated with the wavelet, and then obtain the lifting steps and normalization factors associated with the Laurent polynomials.

```[~,~,LoRz,HiRz] = wave2lp(wv); [lsteps,k] = lp2LS("o",LoRz,HiRz,"s");```

Create a lifting scheme using the lifting steps and normalization factors.

`lscheme = liftingScheme(LiftingSteps=lsteps,NormalizationFactors=k)`
```lscheme = Wavelet : 'custom' LiftingSteps : [3 × 1] liftingStep NormalizationFactors : [3.3461 0.2989] CustomLowpassFilter : [ ] Details of LiftingSteps : Type: 'update' Coefficients: -0.5774 MaxOrder: 0 Type: 'predict' Coefficients: [-2.7990 0.4330] MaxOrder: 1 Type: 'update' Coefficients: 0.3333 MaxOrder: -1 ```

## Input Arguments

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Wavelet type associated with the Laurent polynomials `LoRz` and `HiRz`, specified as one of:

• `"o"` — Orthogonal wavelet

• `"b"` — Biorthogonal wavelet

Data Types: `char` | `string`

Laurent polynomial associated with a lowpass filter, specified as a `laurentPolynomial` object.

Laurent polynomial associated with a highpass filter, specified as a `laurentPolynomial` object.

Factorization mode of lifting steps and normalization factors, specified as one of:

• `"analysis"` — Analysis factorization

• `"synthesis"` — Synthesis factorization

## Output Arguments

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Lifting steps, returned as an array of `liftingStep` structures.

Normalization factors, returned as a 1-by-2 real-valued vector.

Data Types: `double`

## Version History

Introduced in R2021b