Hash arrays of numbers into a string from which you can reconstruct the original values, with configurable precision loss. The generated hashes sort well, so similar input values cause large shared prefixes in hashes.
encode([10, 10, 10]) == 'w07w1z0gs3y0';
encode([10, 11, 10]) == 'w07x1e1cs2yk';
Hash the array [10, -10, 10] and then restore it, using differend
hash sizes.
var sortable = require('sortable-hash');
var hash = sortable.encode([10, -10, 10]);
// => 'p4pp5e9cbbuk'
sortable.decode(hash, 3);
// => [ 9.999942779541016,
// -9.999942779541016,
// 9.999942779541016 ]
var biggerHash = sortable.encode([10, -10, 10], 35);
// => 'p4pp5e9cbbukqnpp5e9cbbukqnpp5e9cb3h'
sortable.decode(biggerHash, 3);
// => [ 10, -10, 10 ]Hash the array values, which may only contain Numbers in the range of
[-100, 100].
options can either be an object with those possible keys:
precision: Length of the resulting hash
or a Number, in which case it sets options.precision.
encode([10], 13) === encode([10], { precision: 13 });Decode string into an Array of Numbers. numValues needs to be the number
of elements initially passed to hash.encode.
With npm do:
$ npm install sortable-hashThis is the idea of geohashes generalized for use with all numeric data and numbers of input fields.
Copyright (c) 2013 Julian Gruber <[email protected]>
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