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]

API

Interfaces

IBucket

Defined in: distributions.ts:22

Properties

| Property | Type | Defined in | | ---------------------------- | ------------------------------ | --------------------------------------------------------------------------------------------------------------------- | | from | number | distributions.ts:24 | | inside | (val: number) => boolean | distributions.ts:26 | | label | string | distributions.ts:23 | | to | number | distributions.ts:25 |

IDistribution

Defined in: distributions.ts:9

Properties

| Property | Type | Defined in | | ---------------------------- | ---------- | --------------------------------------------------------------------------------------------------------------------- | | data | number[] | distributions.ts:11 | | labels | string[] | distributions.ts:10 |

IDistributionArrayItem

Defined in: distributions.ts:14

Properties

| Property | Type | Defined in | | ------------------------------------ | -------- | --------------------------------------------------------------------------------------------------------------------- | | count | number | distributions.ts:16 | | from | number | distributions.ts:18 | | label | string | distributions.ts:15 | | percentage | number | distributions.ts:17 | | to | number | distributions.ts:19 |

ISerieDistribution

Defined in: distributions.ts:29

Properties

| Property | Type | Defined in | | ------------------------------ | ---------- | --------------------------------------------------------------------------------------------------------------------- | | data | object[] | distributions.ts:31 | | labels | string[] | distributions.ts:30 |

Functions

calcBuckets()

function calcBuckets(
  array: number[],
  strict?: boolean,
  numOfBins?: number,
): IBucket[];

Defined in: distributions.ts:57

Calculate the buckets given a data array and an amount

Parameters

| Parameter | 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

calcDiff()

function calcDiff(array: any[], property?: string): number;

Defined in: domain.ts:47

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

Parameters

| Parameter | Type | Description | | ----------- | -------- | ------------------ | | array | any[] | Input array | | property? | string | Property to map by |

Returns

number

Absolute difference between the max and min of an array

calcDistribution()

function calcDistribution(
  array: number[],
  strict: boolean,
  numOfBins?: number,
): IDistribution;

Defined in: distributions.ts:103

Calculates the distribution of an arrays values

Parameters

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

Returns

IDistribution

The distribution

calcDistributionAsArray()

function calcDistributionAsArray(
  array: number[],
  binsStrict?: boolean,
  numOfBins?: number,
): IDistributionArrayItem[];

Defined in: distributions.ts:194

Calculates the distribution of an arrays values and outputs an array

Parameters

| Parameter | 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

calcDistributionWithSeries()

function calcDistributionWithSeries(
  buckets: IBucket[],
  dataGrouped: Record<string, unknown[]>,
  distributionProp: string,
): ISerieDistribution;

Defined in: distributions.ts:136

Calculates the distribution of an array of grouped objects

Parameters

| Parameter | Type | Description | | ------------------ | --------------------------------- | ----------- | | buckets | IBucket[] | | | dataGrouped | Record<string, unknown[]> | | | distributionProp | string | |

Returns

ISerieDistribution

The distribution with labels and data

calcDomain()

function calcDomain(
  array: any[],
  property?: string,
): [number, number] | [any, any];

Defined in: domain.ts:33

Gets the [min, max] value in an array

Parameters

| Parameter | Type | Description | | ----------- | -------- | ------------------ | | array | any[] | Input array | | property? | string | Property to map by |

Returns

[number, number] | [any, any]

The domain

calcHistogram()

function calcHistogram(
  array: any[],
  numberOfBins?: number,
  property?: string,
): number[];

Defined in: distributions.ts:247

Calculates a histogram from array values

Parameters

| Parameter | 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

calcMax()

function calcMax(array: any[], property?: string): number;

Defined in: domain.ts:11

Gets the max value in an array

Parameters

| Parameter | Type | Description | | ----------- | -------- | ------------------ | | array | any[] | Input array | | property? | string | Property to map by |

Returns

number

The maximum value in the array

calcMean()

function calcMean(array: any[], property?: string): undefined | number;

Defined in: averages.ts:102

Gets the mean value for an array

Parameters

| Parameter | Type | Description | | ----------- | -------- | ------------------ | | array | any[] | Input array | | property? | string | Property to map by |

Returns

undefined | number

The mean value

calcMedian()

function calcMedian(array: any[], property?: string): undefined | number;

Defined in: averages.ts:13

Gets an array median

Parameters

| Parameter | Type | Description | | ----------- | -------- | ---------------------- | | array | any[] | Input array | | property? | string | The property to map by |

Returns

undefined | number

The resulting median

calcMin()

function calcMin(array: any[], property?: string): number;

Defined in: domain.ts:22

Gets the min value in an array

Parameters

| Parameter | Type | Description | | ----------- | -------- | --------------- | | array | any[] | Input array | | property? | string | Property to map |

Returns

number

The minimum value in the array

calcPercent()

function calcPercent(toCalc: number, total: number): number;

Defined in: percentages.ts:24

Calculates the percentage of a value, given a total

Parameters

| Parameter | Type | Description | | --------- | -------- | --------------------------- | | toCalc | number | Number to get percentage of | | total | number | Total |

Returns

number

Percentage of the total

calcQuartiles()

function calcQuartiles(
  array: any[],
  property?: string,
): [number, number, number];

Defined in: distributions.ts:224

Gets the quartiles of an array

Parameters

| Parameter | Type | Description | | ----------- | -------- | ------------------ | | array | any[] | Input array | | property? | string | Property to map by |

Returns

[number, number, number]

The quartiles

calcStdDeviation()

function calcStdDeviation<T>(array: T[], property?: string): undefined | number;

Defined in: averages.ts:162

Calculates the standard deviation in an array of numbers

Type Parameters

| Type Parameter | Description | | -------------- | ----------- | | T | |

Parameters

| Parameter | Type | Description | | ----------- | -------- | ------------------------- | | array | T[] | Input array | | property? | string | Property to use for value |

Returns

undefined | number

The standard deviation

calcSum()

function calcSum(array: any[], property?: string): number;

Defined in: operations.ts:11

Gets the sum of the values in an array

Parameters

| Parameter | Type | Description | | ----------- | -------- | ------------------ | | array | any[] | Input array | | property? | string | Property to map by |

Returns

number

The sum

calcVariance()

function calcVariance<T>(array: T[], property?: string): undefined | number;

Defined in: averages.ts:147

Calculates the variance in an array of numbers

Type Parameters

| Type Parameter | Description | | -------------- | ----------- | | T | |

Parameters

| Parameter | Type | Description | | ----------- | -------- | ------------------------- | | array | T[] | Input array | | property? | string | Property to use for value |

Returns

undefined | number

The variance

calcWeightedMean()

function calcWeightedMean(
  array: any[],
  valueProperty: string,
  weightProperty: string,
): number;

Defined in: averages.ts:114

Gets the weighted mean for an array

Parameters

| Parameter | 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

calcWeightedMedian()

function calcWeightedMedian(
  array: any[],
  valueProperty: string,
  weightProperty: string,
): number;

Defined in: averages.ts:44

Gets an array weighted median

Parameters

| Parameter | 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

getMinMaxFromBucket()

function getMinMaxFromBucket(bucketLabel: string): number[];

Defined in: distributions.ts:122

Gets the min and max values for a calcDistribution bucket

Parameters

| Parameter | Type | Description | | ------------- | -------- | ---------------- | | bucketLabel | string | The bucket label |

Returns

number[]

[min, max]

getPercentile()

function getPercentile(
  array: (null | number)[],
  percentile: number,
): undefined | number;

Defined in: percentiles.ts:10

Gets the percentile of an array of values

Parameters

| Parameter | Type | Description | | ------------ | ---------------------- | --------------------------- | | array | (null | number)[] | Array to find percentile of | | percentile | number | Amount between 0 and 1 |

Returns

undefined | number

Percentile

getUntilPercentageThreshold()

function getUntilPercentageThreshold<T>(
  items: T[],
  accessor: (d: T) => number,
  percentageThreshold: number,
): T[];

Defined in: arrays.ts:57

Gets the top % acc items by an accessor

Type Parameters

| Type Parameter | | -------------- | | T |

Parameters

| Parameter | Type | Description | | --------------------- | ---------------------- | ----------------------------------------- | | items | T[] | Items to filter | | accessor | (d: T) => number | The accessor to get a value to accumulate | | percentageThreshold | number | The percentage to stop in (default 80) |

Returns

T[]

getUntilValueThreshold()

function getUntilValueThreshold<T>(
  items: T[],
  accessor: (d: T) => number,
  threshold: number,
): T[];

Defined in: arrays.ts:28

Gets the top items until a cumulative value threshold

Type Parameters

| Type Parameter | | -------------- | | T |

Parameters

| Parameter | Type | Description | | ----------- | ---------------------- | ----------------------------------------- | | items | T[] | Items to filter | | accessor | (d: T) => number | The accessor to get a value to accumulate | | threshold | number | The absolute threshold to stop in |

Returns

T[]

ruleOfThree()

function ruleOfThree(ifThis: number, isThis: number, thenThat: number): number;

Defined in: percentages.ts:9

Performs a simple rule of three

Parameters

| Parameter | Type | Description | | ---------- | -------- | ------------ | | ifThis | number | First param | | isThis | number | First result | | thenThat | number | Second param |

Returns

number

Second result