kernCreate {tigre} | R Documentation

## Initialise a kernel structure.

### Description

Initialise a kernel structure.

### Usage

      kernCreate(x, kernType, kernOptions=NULL)

### Arguments

`x` | If list, array or matrix: input data values (from which kernel will later be computed). If scalar: input dimension of the design matrix (i.e. number of features in the design matrix).
`kernType` | Type of kernel to be created, some standard types are 'rbf', 'white', 'sim' and 'disim'. If a list of the form `list(type='cmpnd', comp=c('rbf', 'rbf', 'white'))` is used a compound kernel based on the sum of the individual kernels will be created. Parameters can be passed to kernels using type `list(type='parametric', options=list(opt=val), realType=...)`, where `realType` is the type that would be used otherwise.
`kernOptions` | (optional) list of kernel options

### Details

`kern <- kernCreate(X, type)` input points and a kernel type.

`kern <- kernCreate(dim, type)` creates a kernel matrix structure given the dimensions of the design matrix and the kernel type.

The *KernParamInit functions perform initialisation specific to different types of kernels. They should not be called directly.

### Value

`kern` | The kernel structure.

### See Also

`kernDisplay, modelTieParam`.

### Examples

    # Create a multi kernel with two rbf blocks with bounded inverse widths
    invWidthBounds <- c(0.5, 2)
    kernType <- list(type="multi", comp=list())
    for (i in 1:2)
      kernType$comp[[i]] <- list(type="parametric", realType="rbf",
                                  options=list(isNormalised=TRUE,
                                    inverseWidthBounds=invWidthBounds))
    kern <- kernCreate(1, kernType)

    # Tie the inverse with parameters of the component RBF kernels
    kern <- modelTieParam(kern, list(tieWidth="inverseWidth"))
    kernDisplay(kern)

[Package tigre version 1.40.0 Index]