R: Arithmetic Mean

mean {base} | R Documentation

## Arithmetic Mean

### Description

Generic function for the (trimmed) arithmetic mean.

### Usage

    mean(x, ...)

    ## Default S3 method:
    mean(x, trim = 0, na.rm = FALSE, ...)

### Arguments

`x` | An R object. Currently there are methods for numeric/logical vectors and date, date-time and time interval objects. Complex vectors are allowed for `trim = 0`, only.
`trim` | the fraction (0 to 0.5) of observations to be trimmed from each end of `x` before the mean is computed. Values of trim outside that range are taken as the nearest endpoint.
`na.rm` | a logical value indicating whether `NA` values should be stripped before the computation proceeds.
`...` | further arguments passed to or from other methods.

### Value

If `trim` is zero (the default), the arithmetic mean of the values in `x` is computed, as a numeric or complex vector of length one. If `x` is not logical (coerced to numeric), numeric (including integer) or complex, `NA_real_` is returned, with a warning.

If `trim` is non-zero, a symmetrically trimmed mean is computed with a fraction of `trim` observations deleted from each end before the mean is computed.

### References

Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.

### See Also

`weighted.mean`, `mean.POSIXct`, `colMeans` for row and column means.

### Examples

    x <- c(0:10, 50)
    xm <- mean(x)
    c(xm, mean(x, trim = 0.10))

[Package base version 3.1.2 Index]