R: Convert Integer to Linear Differential Operator

int2Lfd {fda} | R Documentation

## Convert Integer to Linear Differential Operator

### Description

This function turns an integer specifying an order of a derivative into the equivalent linear differential operator object. It is also useful for checking that an object is of the "Lfd" class.

### Usage

    int2Lfd(m=0)

### Arguments

`m` | either a nonnegative integer or a linear differential operator object.

### Details

Smoothing is achieved by penalizing the integral of the square of the derivative of order `m` over `rangeval`:

m = 0 penalizes the squared difference from 0 of the function

1 = penalize the square of the slope or velocity

2 = penalize the squared acceleration

3 = penalize the squared rate of change of acceleration

4 = penalize the squared curvature of acceleration?

### Value

a linear differential operator object of the "Lfd" class that is equivalent to the integer argument.

### Examples

    # Lfd to penalize the squared acceleration
    # typical for smoothing a cubic spline (order 4)
    int2Lfd(2)

    # Lfd to penalize the curvature of acceleration
    # used with splines of order 6
    # when it is desired to study velocity and acceleration
    int2Lfd(4)

[Package fda version 2.4.8 Index]