Compute-nans NPM

NaNs

Creates a NaN-filled matrix or array.

Installation

$ npm install compute-nans

For use in the browser, use browserify.

Usage

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

nans( dims, opts )

Creates a NaN-filled matrix or array. The dims argument may either be a positive integer specifying a length or an array of positive integers specifying dimensions.

var out;

out = nans( 5 );
// returns [ NaN, NaN, NaN, NaN, NaN ];

out = nans( [2,1,2] );
// returns [ [ [NaN,NaN] ], [ [NaN,NaN] ] ]

The function accepts the following options:

dtype: output data type. The following dtypes are accepted:
- float32
- float64
- generic (default)

By default, the output data structure is a generic array. To output a typed array or matrix, set the dtype option.

var out;

out = nans( 5, {
	'dtype': 'float32'
});
// returns Float32Array( [NaN,NaN,NaN,NaN,NaN] );

out = nans( [3,2], {
	'dtype': 'float64'
});
/*
	[ NaN NaN
	  NaN NaN
	  NaN NaN ]
*/

Notes:

Currently, for more than 2 dimensions, the function outputs a generic array and ignores any specified dtype.

var out = nans( [2,1,3], {
	'dtype': 'float32'
});
// returns [ [ [NaN,NaN,NaN] ], [ [NaN,NaN,NaN] ] ]

Integer arrays are not supported. In JavaScript, NaN values are only represented in floating-point storage formats (IEEE 754).

nans.compile( dims )

Compiles a function for creating NaN-filled arrays having specified dimensions.

var fcn, out;

fcn = nans.compile( [2,1,3] );

out = fcn();
// returns [ [ [NaN,NaN,NaN] ], [ [NaN,NaN,NaN] ] ]

out = fcn();
// returns [ [ [NaN,NaN,NaN] ], [ [NaN,NaN,NaN] ] ]

Notes:

When repeatedly creating arrays having the same shape, creating a customized nans function will provide performance benefits.

Examples

var nans = require( 'compute-nans' ),
	out;

// Plain arrays...

// 1x10:
out = nans( 10 );

// 2x1x3:
out = nans( [2,1,3] );

// 5x5x5:
out = nans( [5,5,5] );

// 10x5x10x20:
out = nans( [10,5,10,20] );

// Typed arrays...
out = nans( 10, {
	'dtype': 'float32'
});

// Matrices...
out = nans( [3,2], {
	'dtype': 'float64'
});

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.

compute-nans v1.0.0