actionscript remove (concat?) sub-arrays - actionscript-3

I have multiple sub-arrays in one huge array - MasterArray- meaning that the sub-arrays are already INSIDE the MasterArray. I would like to "fuse" all of those sub-arrays - to remove those [ ] square brackets.
I would like to avoid the "concat" method because the arrays are already inside the MasterArray. Is there a command/method how to do this?
Thank you.
var englandCities:Array = [London, Manchester, Leeds];
var franceCities:Array = [Paris, Orleans, Avignon];
var europeanCities:Array = [englandCities, franceCities];
I would like to point let's say...to "London" nested in the europeanCities array somehow.
After I try to trace it, it gives me "englandCities", which makes sense.
trace(europeanCities[0]);
// displays "englandCities"
// how can I make it display "London" ?
How can I make the europeanCities array to display "London" ?
I NEED TO REMOVE THOSE SQUARE BRACES from the "europeanCities" array WITHOUT using the concat() thingie...
OKAY let me rephrase this a bit. My master array:
var europeanCities:Array = [englandCities, franceCities];
equals to
[[London, Manchester, Leeds], [Paris, Orleans, Avignon]];
am I right? And now, how to remove the inner brackets in order to get something like this:
[London, Manchester, Leeds, Paris, Orleans, Avignon];
And please, keep in mind, that the array is much longer than englandCities and frenchCities....there are like...30 different Cities.

You can concat those together easily, and it really is the simplest option:
var englandCities:Array = ["London", "Manchester", "Leeds"];
var frenchCities:Array = ["Paris", "Orleans", "Avignon"];
var masterArray:Array = [englandCities, frenchCities];
var europeanCities:Array = new Array();
for each(var country:Array in masterArray) {
europeanCities = europeanCities.concat(country);
}
trace(europeanCities); // London,Manchester,Leeds,Paris,Orleans,Avignon
I'm not sure I understand your reason for avoiding concat for this, unless the issue is it that you don't want to duplicate the values. (So modifying englandCities[0] will also modify europeanCities[0].)
If your cities are Objects rather than primitive Strings, a concatenated Array will work fine. If they are primitives though, there's no way to do this with an Array. You could however write a function to provide similar behaviour like this:
var englandCities:Array = ["London", "Manchester", "Leeds"];
var frenchCities:Array = ["Paris", "Orleans", "Avignon"];
var allCities:Array = [englandCities, frenchCities];
function europeanCities(id:int):String {
var cityID:uint = 0;
while (id > allCities[cityID].length - 1) {
id -= allCities[cityID].length;
cityID++;
}
return allCities[cityID][id];
}
trace (europeanCities(0)); // London
trace (europeanCities(5)); // Avignon

Create an empty array, then traverse the masterArray taking any sub-arrays, and do a concat() for your new array. This will make you another array that's flat, without disturbing master array.

I just write this here because it is possible.
If you insist on not using concat here is one bad solution:
// join elements into a comma delimited string
var s: String = europeanCities.join(',');
// Split the string with delimiter as commas
europeanCities = s.split(',');
Since the subarray elements automatically will be joined with ',' regardless of join delimiter and our join delimiter is already ',' this will work.
But this solution is cpu intensive and not optimal.

Related

Multiple Variable Assignment in Javascript/GAS - Is this the most compact way to do it?

Ok so I have a spreadsheet which we extract a 2d array of values from.
But really I want one variable per line of this 2d array.
The following code does work... but is this the best way to do it?
function testAssignments(){
config = ss.getRange("C2:C6").getValues();//2D Array
result = []
config.forEach(x => result.push(x[0]))
var [a,b,c,d,e] = result;
console.log(a,b,c,d,e);
}
I also tried the line config.forEach(x=> x=x[0]) but that didn't work for some reason.
Use .flat instead of .forEach and .push. If you want a different variable name for each element, there isn't a better way.
const [a,b,c,d,e] = ss.getRange("C2:C6").getValues().flat();//1D Array
//or
const [[a],[b],[c],[d],[e]] = ss.getRange("C2:C6").getValues();

AS3 - getting variable named in order within a function

I am sorry if this is a beginner's question.
I made some Arrays named like map01, map02 and so on... As you can see, I'm making a tile-based flash here. And I need to make a function that when you input a number like: createmap(1); it will get the variable map01 and use the information.
Can I do anything like: var temp:Array = Array(["map" + valueInput]);??
Please tell me if you need anything more.
First, instead of having variables with indices in their names, you should create an array of them. Here, an array of arrays.
So you just have to call var temp:Array = maps[valueInput] as Array;.
If you really don't want to do that and stick with your n variables, you can write
var index:String = valueInput.toString();
if (index.length == 1)
index = "0" + index; //have the index on two digits "01", "02"
var temp:Array = this["map" + index];
Note that it will only work for your 99 first variables (oh God...)

Randomly selecting an object property

I guess a step back is in order. My original question is at the bottom of this post for reference.
I am writing a word guessing game and wanted a way to:
1. Given a word length of 2 - 10 characters, randomly generate a valid english word to guess
2.given a 2 - 10 character guess, ensure that it is a valid english word.
I created a vector of 9 objects, one for each word length and dynamically created 172000
property/ value pairs using the words from a word list to name the properties and setting their value to true. The inner loop is:
for (i = 0; i < _WordCount[wordLength] - 2; i)
{
_WordsList[wordLength]["" + _WordsVector[wordLength][i++]] = true;
}
To validate a word , the following lookup returns true if valid:
function Validate(key:String):Boolean
{
return _WordsList[key.length - 2][key]
}
I transferred them from a vector to objects to take advantage of the hash take lookup of the properties. Haven't looked at how much memory this all takes but it's been a useful learning exercise.
I just wasn't sure how best to randomly choose a property from one of the objects. I was thinking of validating whatever method I chose by generating 1000 000 words and analyzing the statistics of the distribution.
So I suppose my question should really first be am I better off using some other approach such as keeping the lists in vectors and doing a search each time ?
Original question
Newbie first question:
I read a thread that said that traversal order in a for.. in is determined by a hash table and appears random.
I'm looking for a good way to randomly select a property in an object. Would the first element in a for .. in traversing the properties, or perhaps the random nth element in the iteration be truly random. I'd like to ensure that there is approximately an equal probability of accessing a given property. The Objects have between approximately 100 and 20000 properties. Other approaches ?
thanks.
Looking at the scenario you described in your edited question, I'd suggest using a Vector.<String> and your map object.
You can store all your keys in the vector and map them in the object, then you can select a random numeric key in the vector and use the result as a key in the map object.
To make it clear, take a look at this simple example:
var keys:Vector.<String> = new Vector.<String>();
var map:Object = { };
function add(key:String, value:*):void
{
keys.push(key);
map[key] = value;
}
function getRandom():*
{
var randomKey = keys[int(Math.random() * keys.length)];
return map[randomKey];
}
And you can use it like this:
add("a", "x");
add("b", "y");
add("c", "z");
var radomValue:* = getRandom();
Using Object instead of String
Instead of storing the strings you can store objects that have the string inside of them,
something like:
public class Word
{
public var value:String;
public var length:int;
public function Word(value:String)
{
this.value = value;
this.length = value.length;
}
}
Use this object as value instead of the string, but you need to change your map object to be a Dictionary:
var map:Dictionary = new Dictionary();
function add(key:Word, value:*):void
{
keys.push(key);
map[key] = value;
}
This way you won't duplicate every word (but will have a little class overhead).

Splice then re-index array in ActionScript 3

I want to remove the first four indexes from the array using splice(), then rebuild the array starting at index 0. How do I do this?
Array.index[0] = 'one';
Array.index[1] = 'two';
Array.index[2] = 'three';
Array.index[3] = 'four';
Array.index[4] = 'five';
Array.index[5] = 'six';
Array.index[6] = 'seven';
Array.index[7] = 'eight';
Array.splice(0, 4);
Array.index[0] = 'five';
Array.index[1] = 'six';
Array.index[2] = 'seven';
Array.index[3] = 'eight';
I am accessing the array via a timer, on each iteration I want to remove the first four indexes of the array. I assumed splice() would remove the indexes then rebuild the array starting at 0 index. it doesn't, so instead what I have done is created a 'deleteIndex' variable, on each iteration a +4 is added to deleteIndex.
var deleteIndex:int = 4;
function updateTimer(event:TimerEvent):void
{
Array.splice(0,deleteIndex);
deleteIndex = deleteIndex + 4;
}
What type of object is "Array" in the code you have shown? The Flash Array object does not have a property named "index". The Array class is dynamic, which means that it let's you add random properties to it at run time (which seems to be what you are doing).
In any case, if you are using the standard Flash Array class, it's splice() method updates the array indexes automatically. Here is a code example that proves it:
var a:Array = [1,2,3,4,5];
trace("third element: ", a[2]); // output: 3
a.splice(2,1); // delete 3rd element
trace(a); // output: 1,2,4,5
trace(a.length); // ouput: 4
trace("third element: ", a[2]); // output: 4
If I am understanding what you want correctly, you need to use the unshift method of Array.
example :
var someArray:Array = new Array(0,1,2,3,4,5,6,7,8);
someArray.splice(0,4);
somearray.unshift(5,6,7,8);
Also, you are using the Array Class improperly, you need to create an instance of an array to work with first.
The question is confusing because you used Array class name instead of an instance of an array. But as the commenter on this post said, if you splice elements, it automatically re-indexes.
im not sure what you want to do, but Array=Array.splice(0,4) should fix somethin..

AS3 How to make a kind of array that index things based on a object? but not being strict like dictionary

How to make a kind of array that index things based on a object? but not being strict like dictionary.
What I mean:
var a:Object = {a:3};
var b:Object = {a:3};
var dict:Dictionary = new Dictionary();
dict[a] = 'value for a';
// now I want to get the value for the last assignment
var value = dict[b];
// value doesn't exits :s
How to make something like that. TO not be to heavy as a lot of data will be flowing there.
I have an idea to use the toString() method but I would have to make custom classes.. I would like something fast..
Why not make a special class that encapsulates an array, put methods in there to add and remove elements from the array, and then you could make a special method (maybe getValueByObject(), whatever makes sense). Then you could do:
var mySpecialArrayClass:MySpecialArrayClass = MySpecialArrayClass();
var a:Object = {a:3};
var b:Object = {a:3};
mySpecialArrayClass.addElement(a,'value for a');
var value = mySpecialArrayClass.getValueByObject(a);
I could probably cook up a simple example of such a class if you don't follow.
Update:
Would something like this help?
http://snipplr.com/view/6494/action-script-to-string-serialization-and-deserialization/
Update:
Could you use the === functionality? if you say
if ( object === object )
it compares the underlying memory address to see if two objects are the same reference...