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 data frames, numeric vectors and dates. A complex vector is 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 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

For a data frame, a named vector with the appropriate method being applied column by column.
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), integer, numeric or complex, `NA` 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`

### Examples

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

mean(USArrests, trim = 0.2)
```

[Package base version 2.5.0 Index]