# SplineBasis: Creating and SplineBasis Objects. In halpo/obsplines: Orthogonal B-Spline Basis Functions

## Description

The function to create `SplineBasis` and `OrthogonalSplineBasis` Objects

## Usage

 ```1 2 3``` ``` SplineBasis(knots, order=4, keep.duplicates=FALSE) OrthogonalSplineBasis(knots, ...) OBasis(...) ```

## Arguments

 `knots` The full set of knots used to define the basis functions. `order` Order of the spline fit.(degree= order-1) `keep.duplicates` Should duplicate interior knots that could cause computation problem be kept or removed. Defaults to false, which removes duplicate knots with a warning if duplicate interior knots are found. `...` Other arguments either ignored or passed onto other functions.

## Details

`SplineBasis` produces an object representing the basis functions used in spline fitting. Provides a compact easily evaluated representation of the functions. Produces a class of object `SplineBasis`. `OrthogonalSplineBasis` is a shortcut to obtain a set of orthogonalized basis functions from the knots. `OBasis` is an alias for `OrthogonalSplineBasis`. Both provide an object of class `OrthogonalSplineBasis`. The class `OrthogonalSplineBasis` inherits directly from `SplineBasis` meaning all functions that apply to SplineBasis functions also apply to the orthogonalized version.

## Value

Object of class SplineBasis or OrthogonalSplineBasis

## References

General matrix representations for Bsplines KaihuaiQin, The Visual Computer 2000 16:177–186

`SplineBasis`, `spline`, orthogonalsplinebasis-package
 ```1 2 3 4 5 6``` ```knots<-c(0,0,0,0:10,10,10,10) plot(SplineBasis(knots)) obase<-OBasis(knots) plot(obase) dim(obase)[2] #number of functions evaluate(obase, 1:10-.5) ```