sfsmisc (version 1.0-29)

xy.unique.x: Uniqify (X,Y) Values using Weights

Description

Given smoother data $(x_i, y_i)$ and maybe weights $w_i$, with multiple $x_i$, use the unique x values, replacing the $y$'s by their (weighted) mean and updating the weights accordingly.

Usage

xy.unique.x(x, y, w, fun.mean = mean)

Arguments

x,y

numeric vectors of same length. Alternatively, x can be a xy like structure, see xy.coords.

w

numeric vector of non-negative weights -- or missing which corresponds to all weights equal.

fun.mean

the mean function to use.

Value

• Numeric matrix with three columns, named x, y and w with unique x values and corresponding y and weights w.

See Also

e.g., smooth.spline uses something like this internally.

Examples

## simple example:
xy.unique.x(c(1,1,1,2,4), 1:5)
#   x y w
# 1 1 2 3
# 2 2 4 1
# 3 4 5 1