ang {locfit} | R Documentation |

## Angular Term for a Locfit model.

### Description

The `ang()`

function is used in a locfit model formula
to specify that a variable should be treated as an angular
or periodic term. The `scale`

argument of
`locfit()`

is used to set the period.

### Usage

ang(x)

### Arguments

`x` |
numeric variable to be treated periodically. |

### Note

The `scale`

argument to `locfit`

is used to specify
the period divided by *2π* of the term. The default is
`sacle=1`

, giving a period of *2π*.

### References

Loader, C. (1999). Local Regression and Likelihood. Springer, NY (Section 6.2).

### See Also

`locfit`

.

### Examples

# generate an x variable, and a response with period 0.2
x <- seq(0, 1, length=200)
y <- sin(10*pi*x) + rnorm(200) / 5
# compute the periodic local fit. Note the scale argument is period/(2pi)
fit <- locfit(y ~ ang(x), scale=0.2/(2*pi))
# plot the fit over a single period
plot(fit)
# plot the fit over the full range of the data
plot(fit, xlim=c(0,1))

[Package

*locfit* version 1.1-9

Index]