gather

Collect scattering network properties into local workspace

Since R2023a

Syntax

``sn = gather(sf)``

Description

example

````sn = gather(sf)` collects all the wavelet time scattering network, `sf`, properties from the GPU device and returns the gathered `waveletScattering` object `sn`. All properties of the gathered object are stored in the local workspace.```

Examples

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Refer to GPU Computing Requirements (Parallel Computing Toolbox) to see what GPUs are supported.

Load the noisy Doppler signal. Create a wavelet scattering network `gsf` that you can apply to the data.

```load noisdopp gsf = waveletScattering;```

Copy the signal to the GPU.

`gnoisdopp = gpuArray(noisdopp);`

Obtain the scattering feature matrix for the scattering network `gsf` and the data that is on the GPU. Specify the log transformation. Confirm the feature matrix is on the GPU.

```gsmat = featureMatrix(gsf,gnoisdopp); isgpuarray(gsmat)```
```ans = logical 1 ```

Obtain the scaling and wavelet filters used in the scattering network.

`gfil = filterbank(gsf)`
```gfil=3×1 cell array {1×1 struct} {1×1 struct} {1×1 struct} ```

The first element of `gfil` contains the scaling filter used in the computation of the zeroth order scattering coefficients. Subsequent elements of `gfil` contain the wavelet filters and scaling filter for the corresponding filter banks of the scattering decomposition. Confirm all the scaling and wavelet filters are on the GPU.

```[isgpuarray(gfil{1}.phift) isgpuarray(gfil{2}.phift) isgpuarray(gfil{2}.psift) isgpuarray(gfil{3}.phift) isgpuarray(gfil{3}.psift)]```
```ans = 5×1 logical array 1 1 1 1 1 ```

Gather the scattering network. Confirm all the filters in the gathered network `sf` are in the workspace.

```sf = gather(gsf); fil = filterbank(sf); [isgpuarray(fil{1}.phift) isgpuarray(fil{2}.phift) isgpuarray(fil{2}.psift) isgpuarray(fil{3}.phift) isgpuarray(fil{3}.psift)]```
```ans = 5×1 logical array 0 0 0 0 0 ```

Obtain the scattering feature matrix for the scattering network `sf` and the original signal. Specify the log transformation. Confirm the feature matrix is not on the GPU. Confirm the feature matrix is equal to the matrix obtained using the network `gsf`.

```smat = featureMatrix(sf,noisdopp); isgpuarray(smat)```
```ans = logical 0 ```
```xgsmat = gather(gsmat); max(abs(smat(:)-xgsmat(:)))```
```ans = 8.8818e-16 ```

Input Arguments

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Wavelet time scattering network, specified as a `waveletScattering` object.

Version History

Introduced in R2023a