Hash arrays of numbers into sortable strings with variable precision loss
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.
encode10 10 10 == 'w07w1z0gs3y0';encode10 11 10 == 'w07x1e1cs2yk';
Hash the array
[10, -10, 10] and then restore it, using differend
var sortable = require'sortable-hash';var hash = sortableencode10 -10 10;// => 'p4pp5e9cbbuk'sortabledecodehash 3;// => [ 9.999942779541016,// -9.999942779541016,// 9.999942779541016 ]var biggerHash = sortableencode10 -10 10 35;// => 'p4pp5e9cbbukqnpp5e9cbbukqnpp5e9cb3h'sortabledecodebiggerHash 3;// => [ 10, -10, 10 ]
Hash the array
values, which may only contain Numbers in the range of
options can either be an object with those possible keys:
precision: Length of the resulting hash
or a Number, in which case it sets
encode10 13 === encode10 precision: 13 ;
string into an Array of Numbers.
numValues needs to be the number
of elements initially passed to
With npm do:
$ npm install sortable-hash
This is the idea of geohashes generalized for use with all numeric data and numbers of input fields.
Copyright (c) 2013 Julian Gruber <firstname.lastname@example.org>
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