bit-twiddle
===========

This is a collection of miscellaneous bit twiddling hacks ported to JavaScript, mostly taken from here:

* Stanford Bit Twiddling Hacks



Install
=======
Via npm:

npm install bit-twiddle

API

$3

Computes the sign of the integer v. Returns:
* -1 if v < 0
* 0 if v === 0
* +1 if v > 0

$3

Returns the absolute value of the integer v

$3

Computes the minimum of integers x and y

$3

Computes the maximum of integers x and y

$3

Returns true if v is a power of 2, otherwise false.

$3

Returns an integer approximation of the log-base 2 of v

$3

Returns log base 10 of v.

$3

Counts the number of bits set in v

$3

Counts the number of trailing zeros.

$3

Rounds v up to the next power of 2.

$3

Rounds v down to the previous power of 2.

$3

Computes the parity of the bits in v.

$3

Reverses the bits of v.

$3

Interleaves a pair of 16 bit integers. Useful for fast quadtree style indexing. (See wiki: http://en.wikipedia.org/wiki/Z-order_curve )

$3

Deinterleaves the bits of v, returns the nth part. If both x and y are 16 bit, then it is true that:

``javascript
deinterleave2(interleave2(x,y), 0) === x
deinterleave2(interleave2(x,y), 1) === y
`



$3

Interleaves a triple of 10 bit integers. Useful for fast octree indexing.

$3

Same deal as deinterleave2`, only for triples instead of pairs

$3

Returns next combination ordered colexicographically.

Acknowledgements
================
Code is ported from Sean Eron Anderson's public domain bit twiddling hacks page. http://graphics.stanford.edu/~seander/bithacks.html
JavaScript implementation (c) 2013 Mikola Lysenko. MIT License