bench ndarray vs obj

ndarray-vs-obj.js

/*

[email protected]
ndarr : 2030.75ops/sec avg:0.49 max:2 min:0
obj   : 8245ops/sec avg:0.12 max:5 min:0
ndarr : 1958.5ops/sec avg:0.51 max:1 min:0
obj   : 8099.25ops/sec avg:0.12 max:1 min:0

[email protected]
ndarr : 8205.75ops/sec avg:0.12 max:2 min:0
obj   : 27084.25ops/sec avg:0.04 max:2 min:0
ndarr : 8197.5ops/sec avg:0.12 max:2 min:0
obj   : 27161.5ops/sec avg:0.04 max:1 min:0

[email protected]
ndarr : 8508.5ops/sec avg:0.12 max:1 min:0   
obj   : 27552.75ops/sec avg:0.04 max:1 min:0 
ndarr : 8580ops/sec avg:0.12 max:2 min:0     
obj   : 27746.25ops/sec avg:0.04 max:1 min:0 

[email protected]
"ndarr : 34367.5ops/sec avg:0.03 max:2 min:0" 
"obj   : 31713ops/sec avg:0.03 max:1 min:0"
"ndarr : 11812.06ops/sec avg:0.08 max:5573 min:0"
"obj   : 32993.25ops/sec avg:0.03 max:1 min:0"

*/

var ndarray = require('ndarray')

var n = 2e3

var arr = new Float64Array(n*9)
var ndarr = ndarray(arr,[n,9])

function Obj() {
  this.position0 = 1
  this.position1 = 2
  this.position2 = 3
  this.velocity0 = 1
  this.velocity1 = 2
  this.velocity2 = 3
  this.acceleration0 = 1
  this.acceleration1 = 2
  this.acceleration2 = 3
}
Obj.prototype.accelerate = function(x,y,z){
  var p0 = this.position0
  var p1 = this.position1
  var p2 = this.position2
  var v0 = this.velocity0
  var v1 = this.velocity1
  var v2 = this.velocity2
  var a0 = this.acceleration0
  var a1 = this.acceleration1
  var a2 = this.acceleration2
  a0 += x
  a1 += y-50
  a2 += z
  v0 += a0
  v1 += a1
  v2 += a2
  v0 *= .95        
  v1 *= 1
  v2 *= .95
  p0 += v0
  p1 += v1
  p2 += v2
  this.position0     = p0
  this.position1     = p1
  this.position2     = p2
  this.velocity0     = v0
  this.velocity1     = v1
  this.velocity2     = v2
  this.acceleration0 = a0
  this.acceleration1 = a1
  this.acceleration2 = a2
}

var objs = []
for (var i=0;i<n;i++) {
  objs.push(new Obj)
  ndarr.set(i,0,1)
  ndarr.set(i,1,2)
  ndarr.set(i,2,3) 
  ndarr.set(i,3,1)
  ndarr.set(i,4,2)
  ndarr.set(i,5,3)
  ndarr.set(i,6,1)
  ndarr.set(i,7,2)
  ndarr.set(i,8,3)
}

function accelerateNdarr(i,x,y,z) {
  var p0 = ndarr.get(i,0)
  var p1 = ndarr.get(i,1)
  var p2 = ndarr.get(i,2)
  var v0 = ndarr.get(i,3)
  var v1 = ndarr.get(i,4)
  var v2 = ndarr.get(i,5)
  var a0 = ndarr.get(i,6)
  var a1 = ndarr.get(i,7)
  var a2 = ndarr.get(i,8)
  a0 += x
  a1 += y-50
  a2 += z
  v0 += a0
  v1 += a1
  v2 += a2
  v0 *= .95
  v1 *= 1
  v2 *= .95
  p0 += v0
  p1 += v1
  p2 += v2
  ndarr.set(i,0,p0)
  ndarr.set(i,1,p1)
  ndarr.set(i,2,p2)
  ndarr.set(i,3,v0)
  ndarr.set(i,4,v1)
  ndarr.set(i,5,v2)
  ndarr.set(i,6,a0)
  ndarr.set(i,7,a1)
  ndarr.set(i,8,a2)
}

function benchObj(i) {
  for (var j=0;j<2000;j++) objs[i%n].accelerate(i%100,i%100,i%100) 
}
function benchNdarr(i) { 
  for (var j=0;j<2000;j++) accelerateNdarr(i%n,i%100,i%100,i%100) 
}

var t = 4e3
var tt = 1e3
if (process.versions) console.log('node@%s',process.versions.node)
bench('ndarr ',benchNdarr ,t,tt)
bench('obj   ',benchObj   ,t,tt)
bench('ndarr ',benchNdarr ,t,tt)
bench('obj   ',benchObj   ,t,tt)

function bench(name, fn, dur, warmup){ 
  dur = dur || 1000
  name = name || 'unnamed' 
  // name = name+Array(16).slice(name.length).join(' ')
  
  if (warmup) while(warmup--) fn(0)
    
  var now = Date.now()
  var start = now
  var tLast = now
  var time = 0, count = 0, dt = 0, tMin = 0, tMax = 0, i = 0
  
  while (time<dur) {
    fn(i)
    i++
    time = (Date.now()-start)
    sample()
  }
  
  var msPerOp = time/i
  var opsPerSec = 1000/msPerOp
  
  console.log(name+': '
    + parseFloat(opsPerSec.toFixed(2))+'ops/sec'
    + ' avg:'+parseFloat(msPerOp.toFixed(2))
    + ' max:'+tMax
    + ' min:'+tMin
    )
  
  function sample() {
    count++
    now = Date.now()
    dt = now - tLast
    if (count==1) {
      tMin = dt
      tMax = dt
    }
    else {
      tMin = tMin > dt ? dt : tMin
      tMax = tMax < dt ? dt : tMax
    }
    tLast = now
  }
}