summary-collector

Easy summary collector. It collects numbers to named arrays and then computes summary for every array using smry.

Install

npm i summary-collector

Usage

const {collect, summary} = require('summary-collector')(options);

functions:

collect - saves numbers to named arrays. There is two forms:

// 1. using object
collect({
    array1: 123,               //add single number to 'array1'
    array2: [1, 2, 3, 4, 5],   //add many numbers to 'array2'
})
 
// 2. using name and numbers
collect('arr', 1)                 //add single number
collect('arr', 1, 2, 3)           //add many numbers as separate params
collect('arr', [1, 2, 3])         //add many numbers as array
collect('arr', 1, [2, 3], 4, [5]) //add many numbers mixed way
 
// if value is not number - it'll be ignored
collect('test', '1', [null, true], NaN, {}) //nothing happends

summary - returns object with field for every named array created by collect. Each field contains summary for array, computed by smry.

collect('a', 1, 2, 3, 4, 5);
console.log(summary());
/*
{
    a: {
        min: 1,
        max: 5,
        sum: 15,
        len: 5,
        avg: 3,
    },
}
*/

options:

store - initial store (as object with named arrays of numbers).

counters - array of store keys, for wich only sum will computed (and stored/returned as number).

quantile - option for smry. Same syntax.

memory usage tip:

If quantile option is not set - summaries are computing incrementally without storing full arrays in memory. So, if you expect really big arrays, and if you need quantiles only for certain arrays (not for all), it is good idea to use separate pairs of functions. Something like this:

const {collect, summary} = require('summary-collector')(); //save memory
const {collectQ, summaryQ} = require('summary-collector')({quantile: 0.95});

License

MIT