Keygaps

What does this do?

The primary function of this library is to fill in the gaps in data for charting libraries. Many charting libraries, d3 comes to mind, does handle missing data well when dealing with multi-dimensional data.

By multi-dimensional data I simply mean where there are groups of data which should contain a consistent set of x values.

This may look like:

    [
        {company: 'acme', x: 1, y: 99},
        {company: 'acme', x: 2, y: 70},
        {company: 'acme', x: 4, y: 99},
        {company: 'foomaker', x: 1, y: 102},
        {company: 'foomaker', x: 2, y: 99},
        {company: 'foomaker', x: 3, y: 99}
    ]

In the above example the following data is missing:

    [
        {company: 'acme', x: 3, y: ?},
        {company: 'foomaker', x: 4, y: ?}
    ]

Keygaps comes to the rescue here and helps fill in the missing data.

Installation

Node.js

npm install keygaps

Browser

I suggest using Webpack, Browserify, ect. to provide an environment with require.

Usage

fillValues = require('keygaps').fillValues
# Create data with missing keys 
data = [
    {category: 'a', x: 1, y: 10},
    {category: 'b', x: 2, y: 11},
    {category: 'c', x: 1, y: 10},
    {category: 'd', x: 2, y: 10},
]
# Create a valueFunction to tell how to deserialize the key 
# arguments[0] is the ev array passed below 
valueFunction = ->
    obj = {}
    obj['category'] = arguments[0][0]
    obj['x'] = arguments[0][1]
    obj
output = Keygaps.fillValues({
    values: data,
    # Create a keyFunction to know how to group the data 
    keyFunction: (input) -> [input.category, input.x],
    valueFunction: valueFunction
})
 
# object.missingValues 
{
 "a:2": { "category": "a", "x": 2, "y": 0 },
 "b:1": { "category": "b", "x": 1, "y": 0 },
 "c:2": { "category": "c", "x": 2, "y": 0 },
 "d:1": { "category": "d", "x": 1, "y": 0 }
}
# output.values 
[
 { "category": "a", "x": 1, "y": 10 },
 { "category": "b", "x": 2, "y": 11 },
 { "category": "c", "x": 1, "y": 10 },
 { "category": "d", "x": 2, "y": 10 },
 { "category": "a", "x": 2, "y": 0 },
 { "category": "b", "x": 1, "y": 0 },
 { "category": "c", "x": 2, "y": 0 },
 { "category": "d", "x": 1, "y": 0 }
]

Testing

npm run test

Contributing

npm run dev
npm run test

Release process

npm run test
gg c <msg>
npm-release patch

gg represents git goodies, it's just nice. The npm-release docs can be found @ https://github.com/phuu/npm-release