DataWeave Analytics Library

analytics::Statistics

This module provides basic functionality for analyzing
datasets of numeric and non-numeric values.

Index

Functions

Functions

frequencies ↑↑

frequencies<T>(values: Array<T>): Array<{ value: T, occurrences: Number }>

Returns the number of occurrences of each
distinct element in an array.

Parameters

Example

This example shows how frequencies behaves with an array of numbers.

Source

%dw 2.0
output application/json

import frequencies from analytics::Statistics
---
frequencies([1, 2, 11, 1, 1, 2])

Output

[
  {value: 1, occurrences: 3},
  {value: 2, occurrences: 2},
  {value: 11, occurrences: 1}
]

frequencies(values: Null): Null

Helper function that enables frequencies to work with a null value.

mean ↑↑

mean(values: Array<Number>): Number | Null

Returns the mean of an array of numbers,
or null if the array is empty.

Parameters

Example

This example shows how mean behaves with an array of numbers.

Source

%dw 2.0
output application/json

import mean from analytics::Statistics
---
mean([1, 2, 3, 4, 5])

Output

3

Example

This example shows how mean behaves with an empty array.

Source

%dw 2.0
output application/json

import mean from analytics::Statistics
---
mean([]) default "N/A"

Output

"N/A"

mean(values: Null): Null

Helper function that enables mean to work with a null value.

median ↑↑

median(values: Array<Number>): Number | Null

Returns the median value of an array.

If the length of the array is even, returns the average of the two median values.

Parameters

Example

This example shows how median behaves.

Source

%dw 2.0
output application/json

import median from analytics::Statistics
---
median([3, 1, 4])

Output

3

median(values: Null): Null

Helper function that enables median to work with a null value.

mode ↑↑

mode<T>(values: Array<T>): T | Null

Returns the most common value in the array
of values.

If more than one value has the most number of
occurrences, the first value is returned.

Parameters

Example

This example shows how mode behaves with an arbitrary array.

Source

%dw 2.0
output application/json

import mode from analytics::Statistics
---
mode(["hello", "world", "data", "weave", "data"])

Output

"data"

mode(values: Null): Null

Helper function that enables mode to work with a null value.

modes ↑↑

modes<T>(values: Array<T>): Array<T>

Returns the values with the most
number of occurrences.

Parameters

Example

This example shows how modes behaves with an arbitrary array.

Source

%dw 2.0
output application/json

import mode from analytics::Statistics
---
modes(["hello", "world", "data", "weave", "data", "hello"])

Output

["hello", "data"]

modes(values: Null): Null

Helper function that enables modes to work with a null value.

quantilesOf ↑↑

quantilesOf(n: Number, values: Array<Number>): Array<Number> | Null

Returns the points that separate the
values in n parts of equal size.

If the middle point of two points is taken, the function returns the
average of both points.

Parameters

Example

This example shows how the quantilesOf behaves with an arbitrary array.

Source

%dw 2.0
output application/json

import * from analytics::Statistics
---
3 quantilesOf [1, 2, 3, 4, 5]

Output

[2, 4]

quantilesOf(n: Any, values: Null): Null

Helper function that enables quantilesOf to work with a null value.

stdev ↑↑

stdev(values: Array<Number>): Number | Null

Returns the standard deviation of the
given set of values.

The standard deviation is defined as the square root
of the variance.

Parameters

Example

This example shows how stdev behaves with an arbitrary array.

Source

%dw 2.0
output application/json

import stdev from analytics::Statistics
---
stdev([1, 2, 3, 2])

Output

0.7071067811865475244008443621048491

stdev(values: Null): Null

Helper function that enables stdev to work with a null value.

variance ↑↑

variance(values: Array<Number>): Number | Null

Returns the variance of the given set of
values.

Parameters

Example

This example shows how the variance behaves with an arbitrary array.

Source

%dw 2.0
output application/json

import variance from analytics::Statistics
---
variance([1, 2, 3, 2])

Output

0.5

variance(values: Null): Null

Helper function that enables variance to work with a null value.