Sep 9, 2016 · BIT_INDEX: bit_index_in_array --> bit_index_in_dword If i is the number of some bit in the array, BIT_INDEX(i) is the number of that bit in the dword where the bit is stored. And the dword is known via DW_INDEX(). getbit: bit_array, bit_index_in_array --> bit_value putbit: bit_array, bit_index_in_array, bit_value --> 0

When working with Project Euler problems I often need large (> 10**7) bit array's. My normal approach is one of: bool* sieve = new bool[N]; bool sieve[N]; When N = 1,000,000 my program uses 1

Jul 26, 2012 · Then, this code will create a bit array of size 6 million, from bitarray import bitarray bit_array = bitarray(6000000) You can initialize all the bits to zero using. bit_array.setall(0) To set a particular bit, say bit number 25, to 1, do this: bit_array[25]=1

Jan 11, 2011 · Bit Arrays or Bit Vectors can be though as an array of boolean values. Normally a boolean variable needs at least one byte storage, but in a bit array/vector only one bit is needed. This gets handy if you have lots of such data so you save memory at large.

Aug 7, 2011 · The Stanford Javascript Crypto Library (SJCL) provides a Bit Array implementation and can convert different inputs (Hex Strings, Byte Arrays, etc.) to Bit Arrays. Their code is public on GitHub: bitwiseshiftleft/sjcl. So if you lookup bitArray.js, you can find their bit array implementation. A conversion from bytes to bits can be found here.

Apr 1, 2013 · The "proper" way in Java is to use the already-existing BitSet class pointed out by Hunter McMillen. If you're figuring out how a large bit-array is managed purely for the purpose of thinking through an interesting problem, then calculating the position of a bit in an array of bytes is just basic modular arithmetic.

Jul 31, 2014 · Just like the CLR BitArray, the length field refers to the number of bits in the struct and the array field (or Array property) refers to the 32-bit integer array that represents the bits. [CLARIFICATION] I have chosen to take the easy route in my constructors and other methods so that I cannot rely on the unnecessary bits being zeros. For example,

Mar 30, 2010 · You can use BitArray to create a stream of bits from a byte array. Here an example: Here an example: string testMessage = "This is a test message"; byte[] messageBytes = Encoding.ASCII.GetBytes(testMessage); BitArray messageBits = new BitArray(messageBytes);

May 4, 2017 · access_bit(b, 0) returns the least significant bit of the least significant byte assuming big-endian. access_bit(b, 7) returns the most significant bit of the least significant byte assuming big-endian. access_bit(b, 0, 'little') returns the least significant bit of the least significant byte specifying little-endian

I think some of the points made on the site you linked to are not correct by the way. On almost every computer the size of a bit is really one byte (same as a character) because computers can only address a byte not a bit within a byte (if you could then you would only have one eighth of the addressing space you currently have with bytes)