nanquantiles
Computes quantiles for an array ignoring non-numeric values.
Installation
$ npm install compute-nanquantiles
For use in the browser, use browserify.
Usage
var nanquantiles = ;
nanquantiles( arr, num[, opts] )
Computes q-quantiles for an array
ignoring non-numeric values. num
specifies the number of quantiles to compute. For unsorted primitive arrays
,
var unsorted = 4 2 null 5 3 ;var q = ;// returns [ 2, 3.5, 5 ]
The function accepts the following options
:
sorted
:boolean
flag indicating if an inputarray
is sorted in ascending order. Default:false
.accessor
: accessorfunction
for accessing values in an objectarray
.
If the input array
is already sorted in ascending order, set the sorted
option to true
.
var sorted = 2 3 null 4 5 ;var q =;// returns [ 2, 3.5, 5 ];
For object arrays
, provide an accessor function
for accessing array
values
var data =12233null4455;{return d 1 ;}var q =;// returns [ 2, 3.5, 5 ];
Notes
- For an input
array
containing no numeric values, the function returnsnull
. - The function returns the 0th and 100th quantiles; a.k.a., the min and the max. For example, when computing the median,
var data = 11 ;for var i = 0; i < datalength; i++data i = i + 1;console;// returns [ 1, 6, 11 ]
the function returns [1,6,11]
, where min = 1
, max = 11
, and median = 6
. Accordingly, you should expect the output to be an array
with length = q + 1
, where q
is the number of quantiles.
Examples
var nanquantiles = ;var data = 1000 ;for var i = 0; i < datalength; i++if i%2 === 0data i = null;elsedata i = Math;console;
To run the example code from the top-level application directory,
$ node ./examples/index.js
Tests
Unit
Unit tests use the Mocha test framework with Chai assertions. To run the tests, execute the following command in the top-level application directory:
$ make test
All new feature development should have corresponding unit tests to validate correct functionality.
Test Coverage
This repository uses Istanbul as its code coverage tool. To generate a test coverage report, execute the following command in the top-level application directory:
$ make test-cov
Istanbul creates a ./reports/coverage
directory. To access an HTML version of the report,
$ make view-cov
License
Copyright
Copyright © 2015. Philipp Burckhardt.