Euclidean Distance
Computes the Euclidean distance between two arrays.
The Euclidean distance is the straight line distance between two points in Euclidean space.
Installation
$ npm install compute-euclidean-distance
For use in the browser, use browserify.
Usage
var euclidean = ;
euclidean( x, y[, accessor] )
Computes the Euclidean distance between two arrays.
var x = 2 4 5 3 8 2y = 3 1 5 -3 7 2 ;var d = ;// returns ~6.86
For object arrays
, provide an accessor function
for accessing numeric
values.
var x y d;x =122435435862;y ='y':3'y':1'y':5'y':-3'y':7'y':2;{if j === 0return d 1 ;return dy;}d = ;// returns ~6.86
The accessor function
is provided three arguments:
- d: current datum.
- i: current datum index.
- j: array index; e.g., array
x
has index0
, and arrayy
has index1
.
If provided empty arrays
, the function returns null
.
Examples
var euclidean = ;var x = 100y = 100 ;for var i = 0; i < xlength; i++x i = Math;y i = Math;console;
To run the example code from the top-level application directory,
$ node ./examples/index.js
References
- Dahlquist, Germund and Bjorck, Ake. Numerical Methods in Scientific Computing.
- Blue, James (1978) "A Portable Fortran Program To Find the Euclidean Norm of a Vector". ACM Transactions on Mathematical Software.
- Higham, Nicholas J. Accuracy and Stability of Numerical Algorithms, Second Edition.
This module implements a one-pass algorithm proposed by S.J. Hammarling.
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. Athan Reines.