polynomial_basis {basefun} | R Documentation |
Polynomial Basis Functions
Description
Basis functions defining a polynomial
Usage
polynomial_basis(var, coef, ui = NULL, ci = NULL)
Arguments
var |
a |
coef |
a logical defining the order of the polynomial |
ui |
a matrix defining constraints |
ci |
a vector defining constraints |
Details
polynomial_basis
returns a function for the evaluation of
the basis functions with corresponding model.matrix
and predict
methods.
Examples
### set-up basis of order 3 ommiting the quadratic term
pb <- polynomial_basis(numeric_var("x", support = c(0, pi)),
coef = c(TRUE, TRUE, FALSE, TRUE))
### generate data + coefficients
x <- as.data.frame(mkgrid(pb, n = 100))
cf <- c(1, 2, 0, 1.75)
### evaluate basis (in two equivalent ways)
pb(x[1:10,,drop = FALSE])
model.matrix(pb, data = x[1:10, ,drop = FALSE])
### evaluate and plot polynomial defined by
### basis and coefficients
plot(x$x, predict(pb, newdata = x, coef = cf), type = "l")
[Package basefun version 1.1-4 Index]