R: Gradient of the Scaling function (affine case)

affineScalingGrad {DiceKriging} | R Documentation

## Gradient of the Scaling function (affine case)

### Description

Gradient of the Scaling function (marginal in dimension k) of Xiong et al. with respect to eta

### Usage

    affineScalingGrad(X, knots, k)

### Arguments

`X` | an n*d matrix standing for a design of n experiments in d-dimensional space
`knots` | a (K+1) vector of knots parametrizing the transformation. The knots are here the same in all dimensions.
`k` | dimension of the input variables for which the gradient is calculated

### Value

Gradient at X of the scaling transformation of Xiong et al. with respect to eta. In the present version of the function, the gradient calculation is restricted to the case of 2 parameters by dimension (corresponding to the CovAffineScaling class).

### References

Y. Xiong, W. Chen, D. Apley, and X. Ding (2007), Int. J. Numer. Meth. Engng, A non-stationary covariance-based Kriging method for metamodelling in engineering design.

### See Also

`scalingGrad`

[Package DiceKriging version 1.5.5 Index]