scatter.smooth {stats} R Documentation

## Scatter Plot with Smooth Curve Fitted by Loess

### Description

Plot and add a smooth curve computed by loess to a scatter plot.

### Usage

scatter.smooth(x, y = NULL, span = 2/3, degree = 1,
family = c("symmetric", "gaussian"),
xlab = NULL, ylab = NULL,
ylim = range(y, pred\$y, na.rm = TRUE),
evaluation = 50, ..., lpars = list())

loess.smooth(x, y, span = 2/3, degree = 1,
family = c("symmetric", "gaussian"), evaluation = 50, ...)


### Arguments

 x, y the x and y arguments provide the x and y coordinates for the plot. Any reasonable way of defining the coordinates is acceptable. See the function xy.coords for details. span smoothness parameter for loess. degree degree of local polynomial used. family if "gaussian" fitting is by least-squares, and if family = "symmetric" a re-descending M estimator is used. Can be abbreviated. xlab label for x axis. ylab label for y axis. ylim the y limits of the plot. evaluation number of points at which to evaluate the smooth curve. ... For scatter.smooth(), graphical parameters, passed to plot() only. For loess.smooth, control parameters passed to loess.control. lpars a list of arguments to be passed to lines().

### Details

loess.smooth is an auxiliary function which evaluates the loess smooth at evaluation equally spaced points covering the range of x.

### Value

For scatter.smooth, none.

For loess.smooth, a list with two components, x (the grid of evaluation points) and y (the smoothed values at the grid points).

loess; smoothScatter for scatter plots with smoothed density color representation.

### Examples

require(graphics)

with(cars, scatter.smooth(speed, dist))
## or with dotted thick smoothed line results :
with(cars, scatter.smooth(speed, dist, lpars =
list(col = "red", lwd = 3, lty = 3)))


[Package stats version 4.3.0 Index]