rbfKernGradX: Gradient of RBF kernel with respect to input locations.

In gptk: Gaussian Processes Tool-Kit

Description

computes the gradident of the radial basis function kernel with respect to the input positions where both the row positions and column positions are provided separately.

Usage

rbfKernGradX(kern, x1, x2)

Arguments

kern	kernel structure for which gradients are being computed.
x1	row locations against which gradients are being computed.
x2	column locations against which gradients are being computed.

Value

g	the returned gradients. The gradients are returned in a matrix which is numData2 x numInputs x numData1. Where numData1 is the number of data points in X1, numData2 is the number of data points in X2 and numInputs is the number of input dimensions in X.

See Also

rbfKernParamInit, kernGradX, rbfKernDiagGradX.

Examples

## missing

Example output

Loading required package: Matrix
Loading required package: fields
Loading required package: spam
Loading required package: dotCall64
Loading required package: grid
Spam version 2.1-1 (2017-07-02) is loaded.
Type 'help( Spam)' or 'demo( spam)' for a short introduction 
and overview of this package.
Help for individual functions is also obtained by adding the
suffix '.spam' to the function name, e.g. 'help( chol.spam)'.

Attaching package: 'spam'

The following objects are masked from 'package:base':

    backsolve, forwardsolve

Loading required package: maps

gptk documentation built on May 2, 2019, 3:27 p.m.