R: Weighted Mean Direction

weighted.mean.circular {circular} | R Documentation

## Weighted Mean Direction

### Description

Returns the weighetd mean direction of a vector of circular data.

### Usage

    ## S3 method for class 'circular'
    weighted.mean(x, w, na.rm=FALSE,
      control.circular=list(), ...)

### Arguments

`x` | a vector. The object is coerced to class `circular`.
`w` | a numerical vector of weights the same length as `x` giving the weights to use for elements of `x`.
`na.rm` | logical, indicating if `NA`'s should be omitted.
`control.circular` | the attribute of the resulting object.
`...` | further arguments passed to or from other methods.

### Details

Each observation is treated as a unit vector, or point on the unit circle. The resultant vector of the observations is found, and the direction of the resultant vector is returned. An `NA` is returned if the weighted resultant length is less than `.Machine`.

If `w` is missing then all elements of `x` are given the same weight, otherwise the weights coerced to numeric by `as.numeric` and normalized to sum to one.

Missing values in `w` are not handled specially and so give a missing value as the result. However, zero weights are handled specially and the corresponding `x` values are omitted from the computation.

### Value

Returns the weighted mean direction of the data as an object of class `circular` with the attribute given by `control.circular` or from `x` if missed in `control.circular`.

### Author(s)

Claudio Agostinelli

### See Also

`mean.circular`

### Examples

    # Compute the weighted mean direction of a random sample of observations.
    x <- circular(runif(50, circular(0), pi))
    w <- runif(50, 0, 1)
    weighted.mean(x, w)

[Package circular version 0.4-93 Index]