alrico88/math-helper-functions

Helper with misc. math functions such as sums, averages, max, min, etc

math-helper-functions

Installation

Using npm, npm i math-helper-functions.

Using yarn, yarn add math-helper-functions.

Usage

Using import

import { calcSum } from 'math-helper-functions';

const input = [
  { item: 'bookA', count: 3 },
  { item: 'bookB', count: 4 },
];

const totalBooks = calcSum(input, 'count'); // totalBooks is 7

In a CommonJS environment

const { calcDomain } = require('math-helper-functions');

const input = [
  { item: 'bookA', count: 3 },
  { item: 'bookB', count: 10 },
  { item: 'bookC', count: 1 },
];

const domain = calcDomain(input, 'count'); // domain is [1, 10]

Table of contents

Functions

• calcBuckets
• calcDiff
• calcDistribution
• calcDistributionAsArray
• calcDistributionWithSeries
• calcDomain
• calcHistogram
• calcMax
• calcMean
• calcMedian
• calcMin
• calcPercent
• calcQuartiles
• calcStdDeviation
• calcSum
• calcVariance
• calcWeightedMean
• calcWeightedMedian
• getMinMaxFromBucket
• ruleOfThree

Functions

calcBuckets

▸ calcBuckets(array, strict?, numOfBins?): IBucket[]

Calculate the buckets given a data array and an amount

Parameters

Name	Type	Default value	Description
array	number[]	undefined	The data array
strict?	boolean	false	Whether to use real or pretty domain
numOfBins?	number	undefined	Amount of desired buckets

Returns

IBucket[]

The buckets

Export

Defined in

modules/distributions.ts:58

---

calcDiff

▸ calcDiff(array, property?): number

Gets the absolute difference between the max and min value in an array

Parameters

Name	Type	Description
array	any[]	Input array
property?	string	Property to map by

Returns

number

Absolute difference between the max and min of an array

Export

Defined in

modules/domain.ts:48

---

calcDistribution

▸ calcDistribution(array, strict?, numOfBins?): IDistribution

Calculates the distribution of an arrays values

Parameters

Name	Type	Default value	Description
array	number[]	undefined	Input array
strict	boolean	false
numOfBins?	number	undefined	Number of bins to use

Returns

IDistribution

The distribution

Export

Defined in

modules/distributions.ts:105

---

calcDistributionAsArray

▸ calcDistributionAsArray(array, binsStrict?, numOfBins?): IDistributionArrayItem[]

Calculates the distribution of an arrays values and outputs an array

Parameters

Name	Type	Default value	Description
array	number[]	undefined	Array to calc distribution of
binsStrict?	boolean	false	If false, buckets may be rounded [floor, ceil]
numOfBins?	number	undefined	Number of bins to use

Returns

IDistributionArrayItem[]

The distribution as an array of objects

Export

Defined in

modules/distributions.ts:196

---

calcDistributionWithSeries

▸ calcDistributionWithSeries(buckets, dataGrouped, distributionProp): ISerieDistribution

Calculates the distribution of an array of grouped objects

Parameters

Name	Type
buckets	IBucket[]
dataGrouped	Record<string, unknown[]>
distributionProp	string

Returns

ISerieDistribution

The distribution with labels and data

Export

Defined in

modules/distributions.ts:140

---

calcDomain

▸ calcDomain(array, property?): [number, number] | [any, any]

Gets the [min, max] value in an array

Parameters

Name	Type	Description
array	any[]	Input array
property?	string	Property to map by

Returns

[number, number] | [any, any]

The domain

Export

Defined in

modules/domain.ts:36

---

calcHistogram

▸ calcHistogram(array, numberOfBins?, property?): number[]

Calculates a histogram from array values

Parameters

Name	Type	Default value	Description
array	any[]	undefined	Input array
numberOfBins?	number	4	Number of bins to use
property?	string	undefined	Property to map by

Returns

number[]

The histogram

Export

Defined in

modules/distributions.ts:251

---

calcMax

▸ calcMax(array, property?): number

Gets the max value in an array

Parameters

Name	Type	Description
array	any[]	Input array
property?	string	Property to map by

Returns

number

The maximum value in the array

Export

Defined in

modules/domain.ts:12

---

calcMean

▸ calcMean(array, property?): number | undefined

Gets the mean value for an array

Parameters

Name	Type	Description
array	any[]	Input array
property?	string	Property to map by

Returns

number | undefined

The mean value

Export

Defined in

modules/averages.ts:100

---

calcMedian

▸ calcMedian(array, property?): number | undefined

Gets an array median

Parameters

Name	Type	Description
array	any[]	Input array
property?	string	The property to map by

Returns

number | undefined

The resulting median

Export

Defined in

modules/averages.ts:16

---

calcMin

▸ calcMin(array, property?): number

Gets the min value in an array

Parameters

Name	Type	Description
array	any[]	Input array
property?	string	Property to map

Returns

number

The minimum value in the array

Export

Defined in

modules/domain.ts:24

---

calcPercent

▸ calcPercent(toCalc, total): number

Calculates the percentage of a value, given a total

Parameters

Name	Type	Description
toCalc	number	Number to get percentage of
total	number	Total

Returns

number

Percentage of the total

Export

Defined in

modules/percentages.ts:22

---

calcQuartiles

▸ calcQuartiles(array, property?): [number, number, number]

Gets the quartiles of an array

Parameters

Name	Type	Description
array	any[]	Input array
property?	string	Property to map by

Returns

[number, number, number]

The quartiles

Export

Defined in

modules/distributions.ts:227

---

calcStdDeviation

▸ calcStdDeviation<T>(array, property?): number | undefined

Calculates the standard deviation in an array of numbers

Type parameters

Name
T

Parameters

Name	Type
array	T[]
property?	string

Returns

number | undefined

Export

Defined in

modules/averages.ts:155

---

calcSum

▸ calcSum(array, property?): number

Gets the sum of the values in an array

Parameters

Name	Type	Description
array	any[]	Input array
property?	string	Property to map by

Returns

number

The sum

Export

Defined in

modules/operations.ts:12

---

calcVariance

▸ calcVariance<T>(array, property?): number | undefined

Calculates the variance in an array of numbers

Type parameters

Name
T

Parameters

Name	Type
array	T[]
property?	string

Returns

number | undefined

Export

Defined in

modules/averages.ts:142

---

calcWeightedMean

▸ calcWeightedMean(array, valueProperty, weightProperty): number

Gets the weighted mean for an array

Parameters

Name	Type	Description
array	any[]	Input array
valueProperty	string	Property to use for value
weightProperty	string	Property to use for weight

Returns

number

The weighted mean

Export

Defined in

modules/averages.ts:113

---

calcWeightedMedian

▸ calcWeightedMedian(array, valueProperty, weightProperty): number

Gets an array weighted median

Parameters

Name	Type	Description
array	any[]	Input array
valueProperty	string	The property to use as value
weightProperty	string	The property to use as weight

Returns

number

The resulting median

Export

Defined in

modules/averages.ts:45

---

getMinMaxFromBucket

▸ getMinMaxFromBucket(bucketLabel): number[]

Gets the min and max values for a calcDistribution bucket

Parameters

Name	Type	Description
bucketLabel	string	The bucket label

Returns

number[]

[min, max]

Export

Defined in

modules/distributions.ts:125

---

ruleOfThree

▸ ruleOfThree(ifThis, isThis, thenThat): number

Performs a simple rule of three

Parameters

Name	Type	Description
ifThis	number	First param
isThis	number	First result
thenThat	number	Second param

Returns

number

Second result

Export

Defined in

modules/percentages.ts:10