R: Polygonal Basis Function Values

polyg {fda} | R Documentation

## Polygonal Basis Function Values

### Description

Evaluates a set of polygonal basis functions, or a derivative of these functions, at a set of arguments.

### Usage

    polyg(x, argvals, nderiv=0)

### Arguments

`x` | a vector of argument values at which the polygonal basis functions are to evaluated.
`argvals` | a strictly increasing set of argument values containing the range of x within it that defines the polygonal basis. The default is x itself.
`nderiv` | the order of derivative to be evaluated. The derivative must not exceed one. The default derivative is 0, meaning that the basis functions themselves are evaluated.

### Value

a matrix of function values. The number of rows equals the number of arguments, and the number of columns equals the number of basis

### See Also

`create.polygonal.basis`, `polygpen`

### Examples

    #  set up a set of 21 argument values
    x <- seq(0,1,0.05)
    #  set up a set of 11 argument values
    argvals <- seq(0,1,0.1)
    #  with the default period (1) and derivative (0)
    basismat <- polyg(x, argvals)
    #  plot the basis functions
    matplot(x, basismat, type="l")

[Package fda version 2.4.8 Index]