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Detect and replace outliers in data

finds
outliers in `B`

= filloutliers(`A`

,`fillmethod`

)`A`

and replaces them according to `fillmethod`

.
For example, `filloutliers(A,'previous')`

replaces
outliers with the previous non-outlier element. By default, an outlier
is a value that is more than three scaled median absolute deviations (MAD) away
from the median. If `A`

is a matrix or table, then `filloutliers`

operates
on each column separately. If `A`

is a multidimensional
array, then `filloutliers`

operates along the first
dimension whose size does not equal 1.

specifies a method for detecting outliers. For example,
`B`

= filloutliers(`A`

,`fillmethod`

,`findmethod`

)`filloutliers(A,'previous','mean')`

defines an outlier as an
element of `A`

more than three standard deviations from the
mean.

defines outliers as points outside of the percentiles specified in
`B`

= filloutliers(`A`

,`fillmethod`

,'percentiles',`threshold`

)`threshold`

. The `threshold`

argument is a
two-element row vector containing the lower and upper percentile thresholds, such as
`[10 90]`

.

specifies a moving method for detecting local outliers according to a window length
defined by `B`

= filloutliers(`A`

,`fillmethod`

,`movmethod`

,`window`

)`window`

. For example,
`filloutliers(A,'previous','movmean',5)`

identifies outliers as
elements more than three local standard deviations away from the local mean within a
five-element window.

specifies
additional parameters for detecting and replacing outliers using one
or more name-value pair arguments. For example, `B`

= filloutliers(___,`Name,Value`

)`filloutliers(A,'previous','SamplePoints',t)`

detects
outliers in `A`

relative to the corresponding elements
of a time vector `t`

.

`[`

also returns information about the position of the outliers and thresholds computed
by the detection method. `B`

,`TF`

,`L`

,`U`

,`C`

]
= filloutliers(___)`TF`

is a logical array indicating the
location of the outliers in `A`

. The `L`

,
`U`

, and `C`

arguments represent the lower and
upper thresholds and the center value used by the outlier detection method.

Clean Outlier
Data | `fillmissing`

| `ismissing`

| `isoutlier`

| `rmoutliers`