Published
Edited
Jan 4, 2019
1 star
function stringTo32BitBlocks(string){
let result = []
// turn every four bytes into a 32bit number and push to results
for(let i=0;i<string.length; i+=4){
let bytes = string.slice(i, i+4).split('').map(c => c.charCodeAt(0))
let block = (bytes[3] << 16) | (bytes[2] << 12) | (bytes[1] << 8) | bytes[0]
result.push(block)
}
return result
}
function hash(data){
// STEP 1 intialize the internal state
let state = [0xffaaffbb, 0x7fffffff, 0xfabbaafb, 0x40f777a7] // MAGIC NUMBERS
// STEP 2 consume the input data in 32bit blocks (i+=4)
for(let i=0;i<data.length/*STEP 5 if more data repeat STEP 2*/; i+=4){
let bytes = data.slice(i, i+4).split('').map(c => c.charCodeAt(0))
let block = (bytes[3] << 16) | (bytes[2] << 12) | (bytes[1] << 8) | bytes[0]
// STEP 3 and 4 mix the current block with the state and update the state
state = mix(state, block)
}
// STEP 6 FINILISE DATA AND RETURN HASH VALUE
return state.map(n => Math.abs(n).toString(16)).join('')
}
function mix(state, block){
// Step 3 the mix function uses *+-, ^&|, >><< and % to mix the current block in with the state
let select = block % 4
let zero = state[0] + (state[select] * block) ^ state[state[select] % 4] << 3 | block >> 5
let one = zero * (state[2] & state[3]) ^ state[3]
let two = (state[3] >> (zero % 1)) * (zero ^ one)
let three = (state[3] ^ (two << 1)) ^ (state[select] >> 2)
return [zero >> 1, one << 1, two >> 1, three << 1].map(n => n & 0xffffffff)
}
// This is function generates the points plotted above
function hashedLoremToPoints(){
let allHashes = hashedLorem.join('')
let result = []
for(var i=0;i<allHashes.length; i+=16){
// x and y are both 32 bit numbers
result.push({
x: parseInt(allHashes.slice(i, i+8), 16),
y: parseInt(allHashes.slice(i+8, i+16), 16),
})
}
return result
}
Purpose-built for displays of data
Observable is your go-to platform for exploring data and creating expressive data visualizations. Use reactive JavaScript notebooks for prototyping and a collaborative canvas for visual data exploration and dashboard creation.
