README.md

G•M•Y•N•D

A javascript utility library

This library serves for (students) data visualization projects. It provides some data manipulation functions and other utility functions to make the life of javascript programming a bit easier. It's just a set of convenience functions, not a framework.

Some remarks about naming functions and arguments

In this context "data" always refers to a JSON representation of a table, which is an array of simple objects like:

let superheroes = [ 
  {Name:"A-Bomb", Height:203, Weight:441},
  {Name:"Abe Sapien", Height:191, Weight:65},
  {Name:"Abin Sur", Height:185, Weight:90},
  {Name:"Abomination", Height:203, Weight:441},
  {Name:"Absorbing Man", Height:193, Weight:122},
  ...
]

This kind of JSON is usually generated if you convert a CSV-file to JSON. The original CSV of the example above would look like this:

Name,Height,Weight
A-Bomb,203,441
Abe Sapien,191,65
Abin Sur,185,90
Abomination,203,441
Absorbing Man,193,122
...

We will refer to the column titles (e.g. Name, Height, Weight) as properties or props and to the rows as data objects or entries.

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Installation

Either copy ./src/gmynd.js to your project folder or install it in any node.js project:

npm install gmynd

Load the functions into your node script:

const gmynd = require("gmynd");

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Reference

Data manipulation

• sortData(data, props)
• groupData(data, props) -> object
• cumulateData(data, props, [calculations]) -> newData
• mergeData(data1, data2, prop1, [prop2]) -> newData
• intersectData(baseData, filterData, prop1, [prop2]) -> newData
• findAllByValue(data, prop, val) -> newData
• findFirstByValue(data, prop, val) -> object
• deleteIncompleteData(data, props, [emptyValues]) -> newData
• deleteDuplicateData(data, prop, [keepFirst]) -> newData
• filterPropType(data, prop, allowedType) -> newData
• convertPropToNumber(data, prop, [nullNaNs]) -> newData
• convertPropToBoolean(data, prop, [strictMode]) -> newData
• addPropPercentage(data, prop, [propName]) -> newData
• addPropSegment(data, prop, segmentCount, [start], [end], [propName]) -> newData
• addPropRank(data, prop, [propName]) -> newData
• arrayFromProps(obj, props, [fallbackVal]) -> array
• arrayFromPropsInData(arr, props, propName, [deleteProps], [fallbackVal]) -> newData
• renameProps(data, props, names) -> newData (or obj -> newObj)
• deleteProps(data, props) -> newData (or obj -> newObj)
• dataMin(data, prop) -> number
• dataMax(data, prop) -> number
• dataExtremes(data, prop) -> object
• dataSum(data, prop) -> number
• saveData(data, [filename], [pretty])

Array helpers

• arraySum(arr) -> number
• arrayCount(arr, val) -> number
• arrayAverage(arr, [ignoreEmpty]) -> number
• arrayLast(arr, [ignoreEmpty]) -> someValue
• shuffleArray(arr) -> array

Math and utilities

• map(value, low1, high1, low2, high2, [clipping]) -> number
• lerp(value1, value2, t) -> number
• clip(value, min, max) -> number
• random(low, high) -> number
• randomInt(low, high) -> number
• radians(degree) -> number
• degrees(radians) -> number
• distance(x1, y1, x2, y2) -> number
• cartesian(radius, angle) -> object
• polar(x, y) -> object
• circleRadius(area) -> number
• circleArea(radius) -> number
• range(start, stop, [step]) -> array
• duration(date1, date2) -> number
• weekOfYear(date, [returnYear]) -> number or array
• dayOfYear(date) -> number
• isString(value) -> boolean
• isArray(value) -> boolean
• isObject(value) -> boolean
• version() -> string

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Acknowledgements

Example data from

https://www.kaggle.com/dannielr/marvel-superheroes

https://ourworldindata.org/age-structure

https://ourworldindata.org/gender-ratio

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Suggestions? Bugs? File an issue! :)