### Function Reference: `trimmean`

statistics: m = trimmean (x, p)
statistics: m = trimmean (x, p, flag)
statistics: m = trimmean (…, `"all"`)
statistics: m = trimmean (…, dim)
statistics: m = trimmean (…, dim)

Compute the trimmed mean.

The trimmed mean of x is defined as the mean of x excluding the highest and lowest k data values of x, calculated as `k = n * (p / 100) / 2)`, where n is the sample size.

`m = trimmean (x, p)` returns the mean of x after removing the outliers in x defined by p percent.

- If x is a vector, then `trimmean (x, p)` is the mean of all the values of x, computed after removing the outliers.
- If x is a matrix, then `trimmean (x, p)` is a row vector of column means, computed after removing the outliers.
- If x is a multidimensional array, then `trimmean` operates along the first nonsingleton dimension of x.

To specify the operating dimension(s) when x is a matrix or a multidimensional array, use the dim or vecdim input argument.

`trimmean` treats `NaN` values in x as missing values and removes them.

`m = trimmean (x, p, flag)` specifies how to trim when k, i.e. half the number of outliers, is not an integer. flag can be specified as one of the following values:

Value |  | Description
--- | --- | ---
`"round"` |  | Round k to the nearest integer. This is the default.
`"floor"` |  | Round k down to the next smaller integer.
`"weighted"` |  | If k = i + f, where i is an integer and f is a fraction, compute a weighted mean with weight (1 – f) for the (i + 1)-th and (n – i)-th values, and full weight for the values between them.

`m = trimmean (…, `"all"`)` returns the trimmed mean of all the values in x using any of the input argument combinations in the previous syntaxes.

`m = trimmean (…, dim)` returns the trimmed mean along the operating dimension dim specified as a positive integer scalar. If not specified, then the default value is the first nonsingleton dimension of x, i.e. whose size does not equal 1. If dim is greater than `ndims (X)` or if `size (x, dim)` is 1, then `trimmean` returns x.

`m = trimmean (…, vecdim)` returns the trimmed mean over the dimensions specified in the vector vecdim. For example, if x is a 2-by-3-by-4 array, then `mean (x, [1 2])` returns a 1-by-1-by-4 array. Each element of the output array is the mean of the elements on the corresponding page of x. If vecdim indexes all dimensions of x, then it is equivalent to `mean (x, "all")`. Any dimension in vecdim greater than `ndims (x)` is ignored.

See also: mean

Source Code: trimmean