spline_expand {lazy.stat} R Documentation

## Generate Spline Basis

### Description

Generate Spline Basis

### Usage

```spline_expand(x, degree = 3, type = "b", nknots = 0, intercept = 1,
knots = NULL, boundary.knots = NULL, xmin = NULL, xmax = NULL,
rescale = 0, orth = 0, xrange = NULL, xrange0 = NULL,
Xrange0 = NULL, plotbase = 0, printbase = 0)
```

### Arguments

 `x` Input vector. `degree` Degree of polynomial to be used. `type` = "p" for piecewise spline, "b" for b-spline. `nknots` # of knots to be used in [xmin, xmax]. `intercept` = 0 to omit the intercept. `knots` vector consisting of (interior) knots to be used. `boundary.knots` boundary knots for B spline. `xmin` minimum of interior knots. `xmax` maximum of interior knots. `rescale` = 1 to rescale all the basis in [0,1]. `orth` = 1 to orthogonalize the basis. `xrange` new range of x for p-spline or NULL `xrange0` old range of x for p-spline or NULL `Xrange0` old range of X for p-spline or NULL `plotbase` = 1 to plot the result. `printbase` = 1 to print the result.

### Details

When knots are present, it has priority over nknots.

### Value

List of: x
X=length(x) x (nknots+degree+1) spline basis matrix
degree, type, knots,
knots ( interior knots ) , boundary.knots
nobs=nrow(X), nq=ncol(X)

### Examples

```n <- 100
x <- seq(-1,1, length=n)
spline_expand( x, nknots=2, plot=1 )

```

[Package lazy.stat version 0.1.3 Index]