[最適化 Tips] Array, Vector 走査時のイテレーション方法による処理速度の違い
/**
* Copyright muta244 ( http://wonderfl.net/user/muta244 )
* MIT License ( http://www.opensource.org/licenses/mit-license.php )
* Downloaded from: http://wonderfl.net/c/81U9
*/
package {
import flash.display.*;
import flash.geom.*;
import flash.events.*;
import flash.text.*;
import flash.utils.*;
public class Main extends Sprite
{
static private const _NUM_TIMES:uint = 1000000;
private function _init():void
{
_debug(
"各テスト " + _NUM_TIMES + " 回処理させた計算結果 [単位 ： ミリ秒]\n" +
"(誤差は多少生じます)\n"
);
var array:Array = [];
var vector1:Vector.<int> = new Vector.<int>(0, false);
var vector2:Vector.<int> = new Vector.<int>(_NUM_TIMES, false);
var vector3:Vector.<int> = new Vector.<int>(_NUM_TIMES, true);
for (var i:uint = 0; i < _NUM_TIMES; i++) {
array[i] = 0;
vector1[i] = 0;
}
_measure("ループのみ", function ():void
{
for (var i:int = 0; i < _NUM_TIMES; i++) {
}
});
_measure("Array を for で処理", function ():void
{
var e:int;
for (var i:uint = 0, l:uint = array.length; i < l; i++) {
e = array[i];
}
});
_measure("Array を for each で処理", function ():void
{
for each (var e:int in array) {
}
});
_measure("Array を forEach で処理", function ():void
{
array.forEach(function (e:int, i:int, elements:Array):void
{
});
});
_measure("Vector.<int>(0, false) を for で処理", function ():void
{
var e:int;
for (var i:uint = 0, l:uint = vector1.length; i < l; i++) {
e = vector1[i];
}
});
_measure("Vector.<int>(0, false) を for each で処理", function ():void
{
for each (var e:int in vector1) {
}
});
_measure("Vector.<int>(0, false) を forEach で処理", function ():void
{
vector1.forEach(function (e:uint, i:uint, elements:Vector.<int>):void
{
});
});
_measure("Vector.<int>(" + _NUM_TIMES + ", false) を for で処理", function ():void
{
var e:int;
for (var i:uint = 0, l:uint = vector2.length; i < l; i++) {
e = vector2[i];
}
});
_measure("Vector.<int>(" + _NUM_TIMES + ", false) を for each で処理", function ():void
{
for each (var e:uint in vector2) {
}
});
_measure("Vector.<int>(" + _NUM_TIMES + ", false) を forEach で処理", function ():void
{
vector2.forEach(function (e:int, i:int, elements:Vector.<int>):void
{
});
});
_measure("Vector.<int>(" + _NUM_TIMES + ", true) を for で処理", function ():void
{
var e:int;
for (var i:uint = 0, l:uint = vector3.length; i < l; i++) {
e = vector3[i];
}
});
_measure("Vector.<int>(" + _NUM_TIMES + ", true) を for each で処理", function ():void
{
for each (var e:int in vector3) {
}
});
_measure("Vector.<int>(" + _NUM_TIMES + ", true) を forEach で処理", function ():void
{
vector3.forEach(function (e:int, i:int, elements:Vector.<int>):void
{
});
});
_debug("\n結果については言及しませんので, 各自ご判断ください.");
}
private var _field:TextField;
private var _time:uint;
public function Main():void
{
_setup();
_init();
}
private function _measure(title:String, func:Function, ...params):void
{
_time = getTimer();
func.apply(null, params);
_time = getTimer() - _time;
_debug("[ " + title + " ] --> " + _time + " ms");
}
private function _debug(log:String):void
{
_field.appendText(log + "\n");
}
private function _setup():void
{
_field = new TextField();
_field.width = stage.stageWidth - 40;
_field.height = stage.stageHeight - 60;
_field.x = 20;
_field.y = 60;
_field.multiline = true;
_field.wordWrap = true;
var format:TextFormat = _field.defaultTextFormat;
format.font = "_sans";
_field.defaultTextFormat = format;
addChild(_field);
var button:Sprite = new Sprite();
button.graphics.lineStyle(1, 0xBBBBBB);
button.graphics.beginFill(0xEEEEEE);
button.graphics.drawRoundRect(0, 0, 100, 20, 5, 5);
button.graphics.endFill();
addChild(button);
button.x = 20;
button.y = 20;
button.mouseChildren = false;
button.buttonMode = true;
var field:TextField = new TextField();
field.width = 100;
field.height = 20;
field.htmlText = "<p align='center'><font face='_sans'>再計算</span></p>";
button.addChild(field);
button.addEventListener(MouseEvent.CLICK, function ():void
{
_field.text = "";
_init();
});
}
}
}