bit-vec

A lightweight, performant and well documented BitArray/BitVector implementation written in javascript.

Installing

Via NPM: npm install bit-vec --save.

Getting Started

After installing

import BitVector from 'bit-vec';

const bitVec = new BitVector(8);

Example Usage:

import BitVector from 'bit-vec';

const bitVec = new BitVector(8);
bitVec.set(5, 1);
bitVec.test(5); // true
bitVec.flip(5);
bitVec.test(5); // false

// Chaining.
bitVec
  .set(5)
  .set(3)
  .set(1)
  .clearRange(0, 4)
  .test(3); // false

Condensed Documentation

Below is a condensed form of the documentation, each is a function that can be found on the BitVector object, called like so.

const bitVec = new BitVector(42);
bitVec.test(34); // false
bitVec.set(34, 1);
bitVec.test(34); // true

| Method | Parameters | Return | | ----------- | -------- | ------ | | .get(index) | index:Number | Number, 1 if set, 0 if not. | | .set(index) | index:Number | Returns this with the bit set. | | .test(index) | index:Number | Returns Boolean true if index is set, false otherwise . | | .clear(index) | index:Number | Returns this with cleared bit. | | .flip(index) | index:Number | Returns this with flipper bit. | | .count() | None | Returns Number number of indices currently set to 1. | | .setRange(begin, end, value = 1) | begin:Number, end:Number, value:Number | Returns this with bits set.| | .clearRange(begin, end) | begin:Number, end:Number | Returns this with bits cleared. | | .equals(bitVec) | bitVec:BitVector | Returns Boolean true if the two bit vectors are equal, false otherwise. | | .notEquals(bitVec) | bitVec:BitVector | Returns Boolean true if the two bit vectors are different, false otherwise. | | .or(bitVec) | bitVec:BitVector | Returns new BitVector object with the result of the operation.| | .xor(bitVec) | bitVec:BitVector | Returns new BitVector object with the result of the operation.| | .and(bitVec) | bitVec:BitVector | Returns new BitVector object with the result of the operation.| | .not() | None | Returns new BitVector object with the result of the operation. | | .invert() | None | Returns this with updated array. | | .orEqual(bitVec) | bitVec:BitVector | Returns new BitVector object with the result of the operation.| | .xorEqual(bitVec) | bitVec:BitVector | Returns new BitVector object with the result of the operation.| | .andEqual(bitVec) | bitVec:BitVector | Returns new BitVector object with the result of the operation.| | .notEqual() | None | Returns new BitVector object with the result of the operation. | | .isEmpty() | None |Returns Boolean true if the bit vector has no set bits, false otherwise. |

Full Documentation

get

bitVec.get(index)

Performs a get operation on the given index, retrieving the stored value (0 or 1).

Parameters

• index -> Number for index: 0 <= index < bitVec.bits.

Returns

Number, 1 if set, 0 otherwise.

Example

bitVec.get(52); // 0

set

bitVec.set(index)

Performs a set operation on the given index, setting the value to either 0 or 1.

Parameters

• index -> Number for index: 0 <= index < bitVec.bits.
• value -> Number, 0 or 1, defaults to 1.

Returns

Returns BitVector for chaining with the bit set.

Example

bitVec.set(52); // BitVector

test

bitVec.test(index)

Tests whether the given index is set to 1.

Parameters

• index -> Number for index: 0 <= index < bitVec.bits.

Returns

Returns Boolean true if index is set, false otherwise .

Example

bitVec.set(52, 1);
bitVec.test(52); // true

clear

bitVec.clear(index)

Clears the bit at the given index.

Parameters

• index -> Number for index: 0 <= index < bitVec.bits.

Returns

Returns BitVector for chaining with the bit cleared.

Example

bitVec.set(52, 1);
bitVec.test(52); // true

flip

bitVec.flip(index)

Flips the bit at the given index.

Parameters

• index -> Number for index: 0 <= index < bitVec.bits.

Returns

Returns BitVector for chaining with the bit cleared.

Example

bitVec.flip(52);

count

bitVec.count()

Counts the number of set bits in the bit vector.

Parameters

• None

Returns

Returns Number number of indices currently set to 1.

Example

bitVec.count();

setRange

bitVec.setRange(begin, end, value = 1)

Sets a range of bits from begin to end.

Parameters

• begin -> Number for index: 0 <= index < bitVec.bits.
• end -> Number for index: 0 <= index < bitVec.bits.
• value -> The value to set the index to (0 or 1).

Returns

Returns this with bits set.

Example

bitVec.setRange(2, 6);

clearRange

bitVec.clearRange(begin, end)

Clears a range of bits from begin to end.

Parameters

• begin -> Number for index: 0 <= index < bitVec.bits.
• end -> Number for index: 0 <= index < bitVec.bits.

Returns

Returns this with bits cleared.

Example

bitVec.clearRange(2, 6);

equals

bitVec.equals(otherBitVec)

Determines if two bit vectors are equal.

Parameters

• bitVec -> BitVector, instance of BitVector class.

Returns

Returns Boolean true if the two bit vectors are equal, false otherwise.

Example

bitVec.equals(otherBitVec);

notEquals

bitVec.notEquals(otherBitVec)

Determines if two bit vectors are not equal.

Parameters

• bitVec -> BitVector, instance of BitVector class.

Returns

Returns Boolean true if the two bit vectors are equal, false otherwise.

Example

bitVec.notEquals(otherBitVec);

or

bitVec.or(otherBitVec)

Performs the bitwise or operation between two BitVectors and returns the result as a new BitVector object.

Parameters

• bitVec -> BitVector, instance of BitVector class.

Returns

Returns new BitVector object with the result of the operation.

Example

bitVec.or(otherBitVec);

xor

bitVec.xor(otherBitVec)

Performs the bitwise xor operation between two BitVectors and returns the result as a new BitVector object.

Parameters

• bitVec -> BitVector, instance of BitVector class.

Returns

Returns new BitVector object with the result of the operation.

Example

bitVec.xor(otherBitVec);

and

bitVec.and(otherBitVec)

Performs the bitwise and operation between two BitVectors and returns the result as a new BitVector object.

Parameters

• bitVec -> BitVector, instance of BitVector class.

Returns

Returns new BitVector object with the result of the operation.

Example

bitVec.and(otherBitVec);

not

bitVec.not()

Performs the bitwise not operation between two BitVectors and returns the result as a new BitVector object.

Parameters

• None

Returns

Returns new BitVector object with the result of the operation.

Example

bitVec.not();

invert

bitVec.invert()

Inverts this BitVector, alias of .not().

Parameters

• None

Returns

Returns new BitVector object with the result of the operation.

Example

bitVec.invert();

orEqual

bitVec.orEqual(otherBitVec)

Performs the bitwise or operation between two BitVectors and assigns the result to this BitVector.

Parameters

• bitVec -> BitVector, instance of BitVector class.

Returns

Returns this for chaining with the bits set.

Example

bitVec.orEqual(otherBitVec);

xorEqual

bitVec.xorEqual(otherBitVec)

Performs the bitwise xor operation between two BitVectors and assigns the result to this BitVector.

Parameters

• bitVec -> BitVector, instance of BitVector class.

Returns

Returns this for chaining with the bits set.

Example

bitVec.xorEqual(otherBitVec);

andEqual

bitVec.andEqual(otherBitVec)

Performs the bitwise and operation between two BitVectors and assigns the result to this BitVector.

Parameters

• bitVec -> BitVector, instance of BitVector class.

Returns

Returns this for chaining with the bits set.

Example

bitVec.andEqual(otherBitVec);

notEqual

bitVec.notEqual(otherBitVec)

Performs the bitwise not operation between two BitVectors and assigns the result to this BitVector.

Parameters

• bitVec -> BitVector, instance of BitVector class.

Returns

Returns this for chaining with the bits set.

Example

bitVec.notEqual(otherBitVec);

isEmpty

bitVec.isEmpty()

Tests whether this BitVector has any set bits.

Parameters

• bitVec -> BitVector, instance of BitVector class.

Returns

Returns Boolean true if the bit vector has no set bits, false otherwise.

Example

bitVec.isEmpty();

License

See LICENSE file.

Resources

• Bit Array Overview