R: Evaluate an interpolant in a point

interpolant {chebpol} | R Documentation

## Evaluate an interpolant in a point

### Description

An interpolant is a function returned by `ipol` which has prespecified values in some points, and which fills in between with some reasonable values.

### Arguments

`x` | The argument of the function. A function of more then one variable takes a vector. `x` can also be a matrix of column vectors.
`threads` | The number of threads to use for evaluation. All interpolants created by chebpol are parallelized. If given a matrix argument `x`, the vectors can be evaluated in parallel.
`...` | Other parameters. Currently used for simplex linear interpolants with the logical argument `epol` which makes the interpolant extrapolate to points outside the domain. The stalker spline has the argument `blend=c("linear","cubic","sigmoid")` where a blending function can be chosen as described in a vignette. The `"multilinear"` interpolant also has such a blending function.

### Value

A numeric. If more than one point was evaluated, a vector.

### Examples

    grid <- list(x=seq(0,1,length.out=10), y=seq(0,1,length.out=10))
    val <- runif(100)
    dim(val) <- c(10,10)
    ip <- ipol(val, grid=grid, method='fh')
    ip(c(0.3, 0.8))
    ip(matrix(runif(12),2), threads=2)

[Package chebpol version 2.1-2 Index]