This function takes one argument, the number of median absolute deviations within which to accept a particular data point. This is generally more useful than its sister function `within_n_sds` because it is more robust to the presence of outliers. It is therefore better suited to identify potentially erroneous data points.

## Usage

``within_n_mads(n, ...)``

## Arguments

n

The number of median absolute deviations from the median within which to accept a datum

...

Additional arguments to be passed to `within_bounds`

## Value

A function that takes a vector and returns a

`within_bounds` predicate based on the MAD of that vector.

## Details

As an example, if '2' is passed into this function, this will return a function that takes a vector and figures out the bounds of two median absolute deviations (MADs) from the median. That function will then return a `within_bounds` function that can then be applied to a single datum. If the datum is within two MADs of the median of the vector given to the function returned by this function, it will return TRUE. If not, FALSE.

This function isn't meant to be used on its own, although it can. Rather, this function is meant to be used with the `insist` function to search for potentially erroneous data points in a data set.

`within_n_sds`

## Examples

``````test.vector <- rnorm(100, mean=100, sd=20)

custom.bounds.checker(105)     # returns TRUE
#> [1] TRUE
custom.bounds.checker(40)      # returns FALSE
#> [1] FALSE

# same as
#> [1] FALSE

#> [1] TRUE
# because, by default, within_bounds() will accept
# NA values. If we want to reject NAs, we have to
# provide extra arguments to this function
#> [1] FALSE

# or in a pipeline, like this was meant for

library(magrittr)

iris %>%
#>     Sepal.Length Sepal.Width Petal.Length Petal.Width    Species
#> 1            5.1         3.5          1.4         0.2     setosa
#> 2            4.9         3.0          1.4         0.2     setosa
#> 3            4.7         3.2          1.3         0.2     setosa
#> 4            4.6         3.1          1.5         0.2     setosa
#> 5            5.0         3.6          1.4         0.2     setosa
#> 6            5.4         3.9          1.7         0.4     setosa
#> 7            4.6         3.4          1.4         0.3     setosa
#> 8            5.0         3.4          1.5         0.2     setosa
#> 9            4.4         2.9          1.4         0.2     setosa
#> 10           4.9         3.1          1.5         0.1     setosa
#> 11           5.4         3.7          1.5         0.2     setosa
#> 12           4.8         3.4          1.6         0.2     setosa
#> 13           4.8         3.0          1.4         0.1     setosa
#> 14           4.3         3.0          1.1         0.1     setosa
#> 15           5.8         4.0          1.2         0.2     setosa
#> 16           5.7         4.4          1.5         0.4     setosa
#> 17           5.4         3.9          1.3         0.4     setosa
#> 18           5.1         3.5          1.4         0.3     setosa
#> 19           5.7         3.8          1.7         0.3     setosa
#> 20           5.1         3.8          1.5         0.3     setosa
#> 21           5.4         3.4          1.7         0.2     setosa
#> 22           5.1         3.7          1.5         0.4     setosa
#> 23           4.6         3.6          1.0         0.2     setosa
#> 24           5.1         3.3          1.7         0.5     setosa
#> 25           4.8         3.4          1.9         0.2     setosa
#> 26           5.0         3.0          1.6         0.2     setosa
#> 27           5.0         3.4          1.6         0.4     setosa
#> 28           5.2         3.5          1.5         0.2     setosa
#> 29           5.2         3.4          1.4         0.2     setosa
#> 30           4.7         3.2          1.6         0.2     setosa
#> 31           4.8         3.1          1.6         0.2     setosa
#> 32           5.4         3.4          1.5         0.4     setosa
#> 33           5.2         4.1          1.5         0.1     setosa
#> 34           5.5         4.2          1.4         0.2     setosa
#> 35           4.9         3.1          1.5         0.2     setosa
#> 36           5.0         3.2          1.2         0.2     setosa
#> 37           5.5         3.5          1.3         0.2     setosa
#> 38           4.9         3.6          1.4         0.1     setosa
#> 39           4.4         3.0          1.3         0.2     setosa
#> 40           5.1         3.4          1.5         0.2     setosa
#> 41           5.0         3.5          1.3         0.3     setosa
#> 42           4.5         2.3          1.3         0.3     setosa
#> 43           4.4         3.2          1.3         0.2     setosa
#> 44           5.0         3.5          1.6         0.6     setosa
#> 45           5.1         3.8          1.9         0.4     setosa
#> 46           4.8         3.0          1.4         0.3     setosa
#> 47           5.1         3.8          1.6         0.2     setosa
#> 48           4.6         3.2          1.4         0.2     setosa
#> 49           5.3         3.7          1.5         0.2     setosa
#> 50           5.0         3.3          1.4         0.2     setosa
#> 51           7.0         3.2          4.7         1.4 versicolor
#> 52           6.4         3.2          4.5         1.5 versicolor
#> 53           6.9         3.1          4.9         1.5 versicolor
#> 54           5.5         2.3          4.0         1.3 versicolor
#> 55           6.5         2.8          4.6         1.5 versicolor
#> 56           5.7         2.8          4.5         1.3 versicolor
#> 57           6.3         3.3          4.7         1.6 versicolor
#> 58           4.9         2.4          3.3         1.0 versicolor
#> 59           6.6         2.9          4.6         1.3 versicolor
#> 60           5.2         2.7          3.9         1.4 versicolor
#> 61           5.0         2.0          3.5         1.0 versicolor
#> 62           5.9         3.0          4.2         1.5 versicolor
#> 63           6.0         2.2          4.0         1.0 versicolor
#> 64           6.1         2.9          4.7         1.4 versicolor
#> 65           5.6         2.9          3.6         1.3 versicolor
#> 66           6.7         3.1          4.4         1.4 versicolor
#> 67           5.6         3.0          4.5         1.5 versicolor
#> 68           5.8         2.7          4.1         1.0 versicolor
#> 69           6.2         2.2          4.5         1.5 versicolor
#> 70           5.6         2.5          3.9         1.1 versicolor
#> 71           5.9         3.2          4.8         1.8 versicolor
#> 72           6.1         2.8          4.0         1.3 versicolor
#> 73           6.3         2.5          4.9         1.5 versicolor
#> 74           6.1         2.8          4.7         1.2 versicolor
#> 75           6.4         2.9          4.3         1.3 versicolor
#> 76           6.6         3.0          4.4         1.4 versicolor
#> 77           6.8         2.8          4.8         1.4 versicolor
#> 78           6.7         3.0          5.0         1.7 versicolor
#> 79           6.0         2.9          4.5         1.5 versicolor
#> 80           5.7         2.6          3.5         1.0 versicolor
#> 81           5.5         2.4          3.8         1.1 versicolor
#> 82           5.5         2.4          3.7         1.0 versicolor
#> 83           5.8         2.7          3.9         1.2 versicolor
#> 84           6.0         2.7          5.1         1.6 versicolor
#> 85           5.4         3.0          4.5         1.5 versicolor
#> 86           6.0         3.4          4.5         1.6 versicolor
#> 87           6.7         3.1          4.7         1.5 versicolor
#> 88           6.3         2.3          4.4         1.3 versicolor
#> 89           5.6         3.0          4.1         1.3 versicolor
#> 90           5.5         2.5          4.0         1.3 versicolor
#> 91           5.5         2.6          4.4         1.2 versicolor
#> 92           6.1         3.0          4.6         1.4 versicolor
#> 93           5.8         2.6          4.0         1.2 versicolor
#> 94           5.0         2.3          3.3         1.0 versicolor
#> 95           5.6         2.7          4.2         1.3 versicolor
#> 96           5.7         3.0          4.2         1.2 versicolor
#> 97           5.7         2.9          4.2         1.3 versicolor
#> 98           6.2         2.9          4.3         1.3 versicolor
#> 99           5.1         2.5          3.0         1.1 versicolor
#> 100          5.7         2.8          4.1         1.3 versicolor
#> 101          6.3         3.3          6.0         2.5  virginica
#> 102          5.8         2.7          5.1         1.9  virginica
#> 103          7.1         3.0          5.9         2.1  virginica
#> 104          6.3         2.9          5.6         1.8  virginica
#> 105          6.5         3.0          5.8         2.2  virginica
#> 106          7.6         3.0          6.6         2.1  virginica
#> 107          4.9         2.5          4.5         1.7  virginica
#> 108          7.3         2.9          6.3         1.8  virginica
#> 109          6.7         2.5          5.8         1.8  virginica
#> 110          7.2         3.6          6.1         2.5  virginica
#> 111          6.5         3.2          5.1         2.0  virginica
#> 112          6.4         2.7          5.3         1.9  virginica
#> 113          6.8         3.0          5.5         2.1  virginica
#> 114          5.7         2.5          5.0         2.0  virginica
#> 115          5.8         2.8          5.1         2.4  virginica
#> 116          6.4         3.2          5.3         2.3  virginica
#> 117          6.5         3.0          5.5         1.8  virginica
#> 118          7.7         3.8          6.7         2.2  virginica
#> 119          7.7         2.6          6.9         2.3  virginica
#> 120          6.0         2.2          5.0         1.5  virginica
#> 121          6.9         3.2          5.7         2.3  virginica
#> 122          5.6         2.8          4.9         2.0  virginica
#> 123          7.7         2.8          6.7         2.0  virginica
#> 124          6.3         2.7          4.9         1.8  virginica
#> 125          6.7         3.3          5.7         2.1  virginica
#> 126          7.2         3.2          6.0         1.8  virginica
#> 127          6.2         2.8          4.8         1.8  virginica
#> 128          6.1         3.0          4.9         1.8  virginica
#> 129          6.4         2.8          5.6         2.1  virginica
#> 130          7.2         3.0          5.8         1.6  virginica
#> 131          7.4         2.8          6.1         1.9  virginica
#> 132          7.9         3.8          6.4         2.0  virginica
#> 133          6.4         2.8          5.6         2.2  virginica
#> 134          6.3         2.8          5.1         1.5  virginica
#> 135          6.1         2.6          5.6         1.4  virginica
#> 136          7.7         3.0          6.1         2.3  virginica
#> 137          6.3         3.4          5.6         2.4  virginica
#> 138          6.4         3.1          5.5         1.8  virginica
#> 139          6.0         3.0          4.8         1.8  virginica
#> 140          6.9         3.1          5.4         2.1  virginica
#> 141          6.7         3.1          5.6         2.4  virginica
#> 142          6.9         3.1          5.1         2.3  virginica
#> 143          5.8         2.7          5.1         1.9  virginica
#> 144          6.8         3.2          5.9         2.3  virginica
#> 145          6.7         3.3          5.7         2.5  virginica
#> 146          6.7         3.0          5.2         2.3  virginica
#> 147          6.3         2.5          5.0         1.9  virginica
#> 148          6.5         3.0          5.2         2.0  virginica
#> 149          6.2         3.4          5.4         2.3  virginica
#> 150          5.9         3.0          5.1         1.8  virginica

``````