isnan

Computes for each array element whether an element is NaN.

Installation

$ npm install compute-isnan

For use in the browser, use browserify.

Usage

To use the module,

var isnan = require( 'compute-isnan' );

isnan( arr )

Computes for each array element whether an element is NaN. The function returns an array with length equal to that of the input array. Each output array element is either 0 or 1. A value of 1 means that an element is NaN and 0 means that an element is not NaN.

var out = isnan( [ 5, 'beep', 3, 9, true ] );
// returns [ 0, 1, 0, 0, 1 ]

Examples

var isnan = require( 'compute-isnan' );

// Simulate some data...
var data = new Array( 100 ),
	len = data.length,
	rand;

// Division by `undefined` returns NaN...
for ( var i = 0; i < len; i++ ) {
	rand = Math.random()*10;
	if ( rand < 0.5 ) {
		rand = undefined;
	}
	data[ i ] = 100 / rand;
}

var out = isnan( data );

// Count the number of NaNs detected...
var sum = 0;
for ( var i = 0; i < len; i++ ) {
	sum += out[ i ];
}

console.log( 'Count: %d', sum );

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

MIT license.

Copyright

Copyright © 2014. Athan Reines.