xyVector {splines} | R Documentation |
Create an object to represent a set of x-y pairs. The resulting
object can be treated as a matrix or as a data frame or as a vector.
When treated as a vector it reduces to the y
component only.
The result of functions such as predict.spline
is returned as
an xyVector
object so the x-values used to generate the
y-positions are retained, say for purposes of generating plots.
xyVector(x, y)
x |
a numeric vector |
y |
a numeric vector of the same length as |
An object of class xyVector
with components
x |
a numeric vector |
y |
a numeric vector of the same length as |
Douglas Bates and Bill Venables
require(stats); require(graphics)
ispl <- interpSpline( weight ~ height, women )
weights <- predict( ispl, seq( 55, 75, length.out = 51 ))
class( weights )
plot( weights, type = "l", xlab = "height", ylab = "weight" )
points( women$height, women$weight )
weights