level-average

level-average

Calculate rolling averages in a LevelDB.

Example

Store and retrieve rating information:

var level = require('level');
var sub = require('level-sublevel');
var Avg = require('level-average');

var db = sub(level(__dirname + '/db'));
var averages = Avg(db);

averages.push('rating', 2).push('rating', 4);

// then, later on:
averages.get('rating', function(err, value) {
  console.log('rating: %s', value);
  // => rating: 3
});

API

Averages(db)

Create a new averages db. Make sure your db has been given the powers of level-sublevel.

Averages#push(prefix[, id], weight[, fn])

Push weight onto the average for prefix.

Through id you can make some weights overwrite others. Say you let users rate articles in your site, you only would want each user's rating to count one. So, when you use the user's id as id, her rating will only count once.

Averages#get(prefix, fn)

Get the current average for prefix.

Installation

With npm do:

npm install level-average

License

(MIT)

Copyright (c) 2013 Julian Gruber <[e-mail]>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.