Manipulating a struct which is a class property in MATLAB - arrays

I've been trying to work with MATLAB classes & structs in order to develop a traffic simulation. I have not worked actively with MATLAB classes before, so it gets a bit tricky at times. This questions involves manipulating a struct, which is a property of a class.
Top-level access
vehicles_handle = VehiclesHandle;
vehicles_handle.CreateVehicles(InitialTrafficDensity);
vehicles_handle.vehicles(1)
Class definition
classdef VehiclesHandle
%VEHICLESHANDLE Summary of this class goes here
% Detailed explanation goes here
properties
active_vehicles_count
vehicles
end
methods (Access = public)
function obj = VehiclesHandle
obj.active_vehicles_count = 0;
obj.vehicles = struct('lane',0,'position',0,'velocity',0);
end
function obj = CreateVehicles(obj,InitialTrafficDensity)
obj.active_vehicles_count = obj.active_vehicles_count + 1;
obj.vehicles(1).lane = 1;
obj.vehicles(1).position = 3;
obj.vehicles(1).velocity = 3;
obj.vehicles(2).lane = 2;
obj.vehicles(2).position = 3;
obj.vehicles(2).velocity = 3;
end
Now, I can't see the output as expected (which is vehicles_handle.vehicles(1)), I see them the properties of the vehicle 1 as 0's. The situation changes, of course, when I put then in the function VehiclesHandle, but I want to handle creation of vehicles this way.
I know that the code might not be the most efficient way to handle this, but I really do want to learn about handling a struct in this class without pain. Thanks for all the constructive comments and help in advance.

Getting rid of the problem is quite easy:
classdef VehiclesHandle
has to be
classdef VehiclesHandle < handle
And to understand why, please read Comparison of Handle and Value Classes.

Related

Make many dynamic variable (inctance name) with one loop

I have many class in my library almost 300, and I want to generate instance name by loop. In other words I wanna instead of this approach(witch has many code line):
X:This is my problem:
var cm1: Cm1 = new Cm1();
var cm2: Cm2 = new Cm2();
var cm3: Cm3 = new Cm3();
...
use like this approach (less than 10 code lines):
Y:I think this is solution:
for (var i: uint = 1; i < 4; i++)
{
var getChildByName("cm" + i): getChildByName("Cm" + i) = new getChildByName("Cm" + i);
}
but I know above code does not work, is there any way to make them !
-What am I actually trying to solve?
Make many variable by a few line code and save time and size app!
-Why do I have ~300 classes and why are you trying to create them in a loop at once?
This is about to data of request application!
-What do these classes do that you unconditionally need one of each all at the same time?
Because those data would show at first time!
First, it is better to store the classes in an Array or Object rather than an external variable for each item. if you want to access them by name, better to use object:
var classList:Object=new Object();
Then in your loop:
for(var i:uint=1;i<NumberOfClasses;i++){
classList["cm"+i.toString()]=new (getDefinitionByName("Cm"+i.toString()) as Class)();
}
getDefinitionByName is used to make Constructors using String;
Note: if your classes contain a package directory, you should include it. for example:
getDefinitionByName("myclasses.cm.Cm123")();
Then you can access them using Bracket syntax:
classList["cm123"].prop=val;
And don't forget to:
import flash.utils.getDefinitionByName;
I Hope it will help.
EDIT
to use Array instead of object, the loop should be:
for(var i:uint=1;i<NumberOfClasses;i++){
classList[i]=new (getDefinitionByName("Cm"+i.toString()) as Class)();
}
then to access them:
addChild(classList[0]);//0 or any other index;

Instantiation attempted on a non-constructor

I'm trying to make a bomb catching game (I'm actually using the code from the AS3 Classroom in a Book on arrays). As soon as I changed the word fruit to bomb in the code I got error 1007. With the exception of changing basket_mc to eod_mc and fruit to bomb (I used command-F and replaced with case sensitive on) I haven't changed much. It worked with eod_mc, but doesn't with bomb.
var bombArray:Array = new Array(bomb);
var bombsOnstage:Array = new Array();
var bombsCollected:int = 0;
var bombsLost:int = 0;
for (var i:int = 0; i<20; i++) {
var pickBomb = bombArray[int(Math.random() * bombArray.length)];
var bomb:MovieClip = new pickBomb();
addChild(bomb);
bomb.x = Math.random() * stage.stageWidth-bomb.width;// bomb.width is subtracted from the random x position to elimate the slight possibility that a clip will be placed offstage on the right.
bomb.y = Math.random() * -500;
bomb.speed = Math.random() * 15 + 5;
bombsOnstage.push(bomb);
}
eod_mc.addEventListener(MouseEvent.MOUSE_DOWN, dragEod);
stage.addEventListener(MouseEvent.MOUSE_UP, dragStop);
function dragEod(e:Event):void {
eod_mc.startDrag();
}
function dragStop(e:Event):void {
eod_mc.stopDrag();
}
stage.addEventListener(Event.ENTER_FRAME, catchBomb);
function catchBomb(e:Event):void {
for (var i:int = bombsOnstage.length-1; i > -1; i--) {
var currentBomb:MovieClip = bombsOnstage[i];
currentBomb.y += currentBomb.speed;
if (currentBomb.y > stage.stageHeight - currentBomb.height) {
currentBomb.y = 0 - currentBomb.height;
bombsLost++;
field2_txt.text = "Total Bombs Detonated: " + bombsLost;
}
if (currentBomb.hitTestObject(eod_mc)) {
bombsCollected++;
removeChild(currentBomb);
bombsOnstage.splice(i,1);
field1_txt.text = "Total Bombs Caught: " + bombsCollected;
if (bombsCollected >= 20) {
eod_mc.gotoAndStop(20);
} else if (bombsCollected > 15) {
eod_mc.gotoAndStop(15);
} else if (bombsCollected>10) {
eod_mc.gotoAndStop(10);
} else if (bombsCollected>5) {
eod_mc.gotoAndStop(5);
}
}
}
if (bombsOnstage.length <= 0) {
field1_txt.text = "You Win! You have defused the bombs.";
field2_txt.text = "";
stage.removeEventListener(Event.ENTER_FRAME, catchBomb);
}
if (bombsLost >= 20) {
field1_txt.text = "Sorry you lose. You have lost your foot!";
field2_txt.text = "";
stage.removeEventListener(Event.ENTER_FRAME, catchBomb);
for (var j:int = bombsOnstage.length-1; j > -1; j--) {
currentBomb = bombsOnstage[j];
removeChild(currentBomb);
bombsOnstage.splice(j,1);
}
}
}
Maybe to avoid making your programming life more twisted than it is now...
There are objects and classes in programming, a class is a description of a set of objects, say "table" (or, as it's better to differ in names for classes and variables, "Table", first letter capitalized) is a name of a class. An instance or an object is a structure that belongs to one or more classes, with Object being the topmost, as everything in programming is either an object or a "simple variable", that is, a number, a true/false, a string of characters (these are object types in AS3 too, though, Number, Boolean, String, but these generally not need to be instantiated via new) or probably some other simple type I don't remember right now.
Classes have properties and methods. A property is something that can be requested off any object of the class, say "height" for tables. Properties can be of any type, including nested objects, depending on what your base class is. Say stage in AS3 is a property of any DisplayObject which is used to get the only Stage object there is at runtime[1]. Methods are what any object of a class can be told to do. Say, bombs fall, explode, MovieClips can be told to stop(), etc. You write class code keeping in mind that all of the objects of this class will have to behave exactly like you've written, but since they can differ in properties, you can give them conditional behavior. For example, if a bomb has already exploded, it cannot blow up once more.
A variable, whether a property or a standalone var (if you declare one in a function) is a reference to an object of a given type. Say var i:int refers to some kind of an integer. Simple type vars are containers instead, that is, i=2; will place a 2 in the referred integer, and i=j; will copy the value from j into i, while var theStage:Stage=this.stage will instead create a reference to an existing object, and if that object will change, the reference will give you the changed object instead of its previous state. An array is a collection of variables, reachable by indexes, in AS3 they don't have to be of one type, and a Vector is a typed array.
Next, the lifetime of objects. An object only lives while there's an active reference to it, whether in a property of another alive object, or in a visible variable, or in an event listener (AS3 specific). An object is created via new ClassName(<parameters>), lives while you can reach it somehow, and is destroyed once you have no active links to it and Flash player decides to run garbage collector. Prior to this programmers had to deallocate objects themselves, a rudiment can be seen at BitmapData.dispose(). So, in order to avoid Flash player to run out of free memory, take full control over creation and destruction of links. You don't need to care for simple vars, they are being cared for by Flash player.
A lot of basic functions for interactions has already been implemented in AS3, look for them and examples of how they work in Adobe's manual, navigate through packages in the lower left, most of the interactive stuff is in flash.display package, refer to other packages as necessary.
Hope this will bring you some insight into programming basics.
[1]: There is one stage unless you're doing a load of an SWF, then there could be more, one Stage per one SWF.

AS3: Creating and accessing movieclips from an array

I know there are quite similar questions here, but I haven't found the proper details. What would be helpful is definitely an explanation of the problems, and perhaps a base example, that anyone who searches later may be able to apply. (Not asking that you write it for me, I just find the examples helpful) I don't want to upset anyone and am kind of worried to post in a forum...
I am wondering alternatives to creating a screen based off tiles created from an array. I have been having an issue myself trying to access the movieclips that have been placed on screen, and trying to trace to find a way to reference them hasn't been working.
Anyway, take something basic like an array, and connecting it to movieclips, then how to access the movieclip itself once done. So I have been working on this, and used many different online resources, so I'm sure a lot of this is going to look familiar, just in a much messier way.
This takes the array to make the movieclips appear (Im sure at least one part in here is unnecessary, and I'm thinking I'm doing something wrong here that makes it not work out later) So this works, but feels pretty bulky.
Both are from the same main class file.
function makeWorld (anyMap, tileW, tileH) {
var worldWidth = anyMap[0].length;
var worldHeight = anyMap.length;
var MAP = this.addChild(new mapHolder());
function tiler(MAP, i, j, tileW, tileH, tile)
{
MAP.addChild(tile);
tile.x = (j * tileW);
tile.y = (i * tileH);
}
for (var i = 0; i < worldWidth; ++i) {
for (var j = 0; j < worldHeight; ++j) {
var curTile:int = anyMap[i][j];
if (curTile == 101) {
var tile1 = new tileGround();
tiler (MAP, i, j, tileW, tileH, tile1);
...
else {
var tile3 = new empty();
tiler (MAP, i, j, tileW, tileH, tile3);
}
}}}
Then there is attempting to reference it, where I'm having the issue. I don't know what to call this.MAP.tileGround by, and I have tried many things. I've read it's not such a good idea to reference by name when not very advanced so I wanted to avoid that sort of thing too.
addEventListener (Event.ENTER_FRAME, hits);
function hits (event:Event) {
var tileCatchG:MovieClip = this.MAP.tileGround;
if(tileCatchG.hitTestPoint(this.MAP.Char.x + leftBumpPoint.x, this.MAP.Char.y + leftBumpPoint.y, true)){
leftBumping = true;
} else {
leftBumping = false;
}
...
}
Thank you!
In looking over what you're doing a second time it would appear that you should have a reference to the 2-indexed array that represents the map.
You can create a regular (single indexed) Array at the top of the file like
public var tileArray:Array = [];
Then where you create them push them into the array
var tile1 = new tileGround();
tileArray.push(tile1);
then to reference them all you can just run a simple loop
for each(var tile:MovieClip in tileArray)
{
//Do stuff
if(tile instanceof tileGround)
{
//Do stuff specific to tileGround
}
}

Actionscript 3.0 Get all instances of a class?

I got a ton of movieclips in a class. Is there a more efficient way to apply a function to every instance in the class other than this?
var textArray:Array = [
interludes.interludeIntro.interludeBegin1,
interludes.interludeIntro.interludeBegin2,
interludes.interludeIntro.interludeBegin3,
interludes.interludeIntro.interludeBegin4,
interludes.interludeIntro.interludeBegin5,
interludes.interludeIntro.interludeBegin6,
interludes.interludeIntro.interludeBegin7,
//... ... ...
interludes.interludeIntro.interludeBegin15
];
for each (var interludeText:MovieClip in interludeBeginText)
{
interludeText.alpha = 0 //clear all text first
}
Also for some reason this doesn't work:
interludes.interludeIntro.alpha = 0;
It permanently turns that class invisible, even if I try to make specific instances visible later with:
interludes.interludeIntro.interludeBegin1.alpha = 1;
I have NO idea why the above doesn't work. I want to turn every single instance in the class interludeIntro invisible, but I want to turn specific instances visible later.
(btw I have no idea how to insert code on this website, pressing "code" doesn't do anything, so pardon the bad formatting)
I'm not really sure what you're asking, but what may be useful is that, in ActionScript you can refer to properties by name, like myObject["someProperty"].
Using that, you can iterate over properties if they follow some naming scheme, so for example:
for (var i:int = 1; i <= 15; i ++)
interludes.interludeIntro["interludeBegin" + i].alpha = 0;
That iterates over interludes.interludeIntro.interludeBegin1 through ...15 and sets their alpha properties to 0.
When you do that:
interludes.interludeIntro.alpha = 0;
you turn the movie clip and all its children invisible.
So later when you do that:
interludes.interludeIntro.interludeBegin1.alpha = 1;
You make the movie clip visible, but since its parent is still invisible, you don't see anything. The solution is to loop through the movie clips and make each of them invisible/visible.
// Keep the parent visible at all time
interludes.interludeIntro.alpha = 1;
for (var i:int = 0; i < textArray.length; i++) {
textArray[i].alpha = 0;
}
// Now this will work:
interludes.interludeIntro.interludeBegin1.alpha = 1;

multiple instances of the same object spaced out using a loop is only creating one

I had a hard time trying to word my question properly, so i'm sorry if it seems confusing. Also i'm using the flixel library in flash builder. It may not be that important butcause probably anyone that knows a little more than me or even a little AS3 could probably see what i'm doing wrong.
Anyway, what i'm trying to do is basically create 10 instances of this square object I made. all I have to do is pass it an x an y coordinate to place it and it works. so ive tested if i just do:
var testsquare:Bgsq;
testsquare = new Bgsq(0,0);
add(testsquare);
it works fine and adds a square at 0,0 just like i told it to, but i want to add 10 of them then move the next one that's created 25 px to the right (because each square is 25px)
my problem is that I only ever see 1 square, like it's only making 1 instance of it still.
anyone possibly have an idea what I could be doing wrong?
var counter:int = 0;
var bgsqa:Array = new Array;
for (var ibgs:int = 0; ibgs < 10; ibgs++)
{
bgsqa[counter] = new Bgsq(0,0);
bgsqa[counter].x += 25;
add(bgsqa[counter]);
counter++;
}
There's a lot you're doing wrong here.
First off, you're using a pseudo-iterator (counter) to access array elements through a loop instead of, well, using the iterator (ibgs).
Second, I don't see anything in the array (bgsqa) you're iterating through. It's no wonder you're having problems. Here's what you should do.
var bgsqa:Array = [];
for(var i:int=0;i<10;i++)
{
var bgsq:Bgsq = new Bgsq(i * 25, 0);
add(bgsq);
bgsqa.push(bgsq);
}
That should probably do it if your post is accurate.
for (var ibgs:int = 0; ibgs < 10; ibgs++)
{
bgsqa[counter] = new Bgsq(0,0);
bgsqa[counter].x = counter * 25;
add(bgsqa[counter]);
counter++;
}
They start at 0, so applying += is simply adding 25 to 0. This should do the trick.

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