multiset-jaccard

#Multiset-Jaccard

A Jaccard Index calculator supporting multi-set

##Installation
``
$ npm install --save multiset-jaccard
`

##How to use

Get Jaccard-index between two arrays
`javascript
var jaccard = require('multiset-jaccard');

var A = ["Apple","Banana","Apple","Cherry","Mango"]; // multi-set
var B = ["Apple","Cherry","Melon","Orange"];

var index = jaccard.index(A, B);
/*
result : 0.2857142857142857
*/

// Below is asynchronous method
jaccard.index(A, B, function (err, index) {
console.log("result : ", index);
});
/*
result : 0.2857142857132857
*/
`

If you want to make Counter, make instances like this.
`javascript
var A = ["Apple","Banana","Apple","Cherry","Mango"];
var A_Counter = new jaccard.Counter(A);
/*
A_Counter.elements : {{"Apple" : 2}, {"Banana" : 1}, {"Cherry" : 1}, {"Mango" : 1}}
A_Counter.keys() returns ["Apple","Banana","Cheery","Mango"]
A_Counter.values() returns [2,1,1,1]
*/

`
And you can get sum of Counters and product of Counters like this.
`javascript
var A = ["Apple","Banana","Apple","Cherry","Mango"]; // multi-set
var B = ["Apple","Cherry","Melon","Orange"];
var A_Counter = new jaccard.Counter(A);
var B_Counter = new jaccard.Counter(B);

var sum = jaccard.sum(A_Counter, B_Counter);
var product = jaccard.product(A_Counter, B_Counter);

/*
sum : {{"Apple": 2}, {"Banana": 1}, {"Cherry": 1}, {"Mango": 1}, {"Melon": 1}, {"Mango": 1}}
product : {{"Apple": 1}, {"Cherry": 1"}}
*/

`

You can get same result by putting arrays. (0.1.2v)
`javascript
var sum = jaccard.sum(A, B);
var product = jaccard.product(A, B);
``