# wavsupport

Wavelet support

## Syntax

``[LB,UB] = wavsupport(wname)``
``B = wavsupport(wname)``

## Description

example

````[LB,UB] = wavsupport(wname)` returns the lower bound, `LB`, and upper bound, `UB`, of the support for the wavelet specified by `wname`.```
````B = wavsupport(wname)` returns the lower and upper bounds of the support of the wavelet.```

## Examples

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Return the lower bound and upper bound of the support for the Haar wavelet.

`[LB,UB] = wavsupport('haar')`
```LB = -0.5000 ```
```UB = 0.5000 ```

The length of the Haar wavelet filter is 2. Compare `LB` and `UB` to the lower and upper bounds for orthogonal and biorthogonal wavelets (type 1 and type 2).

```LF = 2; LowerBound = -0.5*(LF-1)```
```LowerBound = -0.5000 ```
`UpperBound = 0.5*(LF-1)`
```UpperBound = 0.5000 ```

Return the lower bound and upper bound of the support for the complex-valued Gaussian wavelet.

`[LB,UB] = wavsupport("cgau3")`
```LB = -5 ```
```UB = 5 ```

## Input Arguments

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Wavelet, specified by a character vector or string scalar. The wavelet must be recognized by `wavemngr`.

Example: `"db4"`

Data Types: `char` | `string`

## Output Arguments

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Wavelet support, returned as scalars. `LB` and `UB` are the lower and upper bounds, respectively, of the support.

• For real-valued wavelets with and without scaling functions and complex-valued wavelets without scaling functions (wavelets type 3,4, and 5), the bounds indicate the effective support of the wavelet.

• For orthogonal and biorthogonal wavelets (type 1 and type 2 respectively), the lower and upper bounds are ```LB = -0.5*(LF-1)``` and ```UB = 0.5*(LF-1)```, where LF is the length of the wavelet filter.

Data Types: `double`

Support of the wavelet, returned as a vector: ```B = [LB,UB]```.

Data Types: `double`

## Version History

Introduced in R2010b