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