# Use Array.slice To Divide The Array Into Two Equal Sized Arrays?

Jul 21, 2011

is this correct

var mid = math.floor((0 + array.length)/2)

from here you could use array.slice to divide the array into two equal sized arrays?

## Array.slice() Not Creating An Independent Copy.

Mar 11, 2007

Alright, am I missing something?

I create a 2D array like so:

var blah = [];
blah[0] = ['one', 'two', 'three'];
blah[1] = ['four', 'five', 'six'];

Then I *attempt* to create an independent copy based on all of the pages I have read that
said it was as so:

var copy_of_blah = blah.slice(); // does not create independent copy
var copy_of_blah = blah.slice(0); // nor does this

I tested it by immediately changing either:

blah[0][0] = '' // "one" is now ''

*or*

copy_of_blah[0][0] = '' // "one", is again, ''

And of course both reflect changes upon the other.

Is it possible to create an independent copy of an array without having to write a
function that dumps the contents into a new array?

## Tried To Slice The Array And Pass It As Arguments Didn't Get Passed?

Oct 5, 2010

<html>
<title>Variable - Examples 1</title>

[code]....

## Output Two Maximum Numbers Of An Array If They Are Equal?

Jun 20, 2010

How can i output two maximum numbers of an array if they are equal?

var flower["roses", "violets", "buttercups", "daisies"];
var flowerAmounts[9, 8, 3, 9];

Output should be: The maximum amount of flowers is 9. There are 9 roses and 9 daisies.

## Why Is The Callwhy Is The Slice Method Only A Method Of An Array Instance?

Jan 31, 2011

Why is the callwhy is the slice method only a method of an Array instance? The reason why I ask is because if you want to use it for the arguments property of function object, or a string, or an object, or a number instance, you are forced to use Array .prototype slice.call(). And by doing that, you can pass in any type of object instance (Array, Number, String, Object) into it. So why not just default it as a method of all object instances built into the language?In other words, instead of doing this:

function Core(){
var obj = {a : 'a', b : 'b'};
var num = 1;[code]....

//right now none of the above would work but it's more convenient than using the call alternative.

}
Core('dom','event','ajax');

Why did the designers of the javascript scripting language make this decision?

## Array Undefined After Setting Equal To Values Of Several <INPUT> Fields

Apr 7, 2009

I keep getting <undefined> when I alert out the value of my array 'fadeimages1'. Using php/mysql I retrieve filenames from a directory and create <INPUT> fields to store the filenames. In the javascript portion of the code, I use getElementsByName() to retrieve all of the <INPUT> fields. I then declare an array, 'fadeimages1'. Next, using a for loop I try to copy the values from the <INPUT> fields into the array 'fadeimages1'. When I alert out the length and value variable for each <INPUT> field, I get the correct filename, but after trying to store the value into 'fadeimages1' array, I get value is <undefined> when I alert it out. BTW, the following code uses 'fadeimages1.push()', but I also tried 'fadeimages1[i]=...'. Both result in <undefined> values.

[Code]....

## Merge The Two Arrays Into A Third Array

Mar 28, 2009

I've been given two arrays:

arr1 = [1,8,9,12]
arr2 = [2,3,10,11,13]

My task was to merge the two arrays into a third array. Done, no problem, merged then sorted a new array. I understand there is a way to merge the two without using "merge" then "sort" functions. My reference material doesn't go into it, and I can't find an example of how this would work. I think there would be a way to do it using a for loop and then "push", but I could be way off.

Can anyone tell me how they could see merging two without using the merge then sort? And what would be the advantage to doing it this alternate way as opposed to using merge? Is there a case where it would be preferable? I'm so new at this that I can't fathom doing anything other than merge.

## Declaring / Using Array Of Arrays

Mar 27, 2010

(the "code" below is pseudo code, just to get the idea across)

Here's what I currently have:

var bill = new array[20];
var sam = new array[20];
var nancy = new array[20];
var Oscar = new array[20];

I'm assigning objects to them (ie Oscar[5] = new objLabel() This seems like a kluge, however. Here's what I'd like (again, pseudo-code)

var Objects = {bill:null; sam:null; nancy:null; Oscar:null};
var theObject = new Array of Objects[20];
// yes: i know that's wrong... and that's the part I'm having trouble with

so that I can do something like:

[Code]....

Just seems to me that keeping a single array of multiple objects is likely to be less error-prone than multiple arrays of single objects... But I don't have the syntax right... or can it be done in JS? If it's doable, would someone be kind enough to show me how to declare and access that example?

## Passing An Array Of Arrays To Function

Nov 8, 2010

I was having some trouble with 2D arrays (or array of arrays). Essentially, the array has 100 rows, with two columns. The first column of every row holds a name, and the second holds a sales amount. With the use of a do while loop, the user can continuously add up to 100 names and sales amounts. After all the information the user wishes to add is stored into the 2D array I'm attempting to pass that very same 2D array as a parameter to a function called printRow as can be seen in the code below: Note: the function call and the actual function are found in two separate javascripts.

[Code]...

## Creating A New API - Use A Single Array Or Multiple Arrays?

Jan 8, 2011

I have a choice when creating a new API that I would like other peoples opinions on. Do I use a single Array or Multiple arrays such as: array[1][1] = "ID[56]NAME[Hello World]START[10]"; OR

ID[1][1] = 56;
Name[1][1] = "Hello World";
Start[1][1] = 20;

The API is used for animations so is very heavy work, but would using around 15 multidimensional arrays be too much and a single one be preferable???

## Ajax :: Objects With Arrays That Should Be Transferred As Php Array

Apr 10, 2011

I'm have some javascript objects with arrays that should be transferred as php array.Its posted by ajax httpRequest.How can I return php array, from the javascript?

## Looping Through Arrays: For/in Versus Using Array Length?

Aug 3, 2009

I'm a JS beginner and I find looping through arrays with for/in is very easy. Yet I find lots of code examples where array length is used instead of for/in and I'm thinking to myself, why do it this (somewhat) hard(er) way?

## Sum Different Arrays And Display The Total In A Array Field In The Form Itself?

Mar 9, 2011

i have a form with arrays, I want to sum different arrays and display the total in a array field in the form itself.i have this code

<form>
do {
\$x++;

[code]....

## JS Arrays In Storing Input Frm Form Into Array / Displaying Result

Mar 18, 2009

need urgent help with javascript arrays. I need to store the checked value of the radiobutton into an array and then display the result from that array.I have created an empty array to store the input from the textbox of the form using the JS insert() function and then used show() function to display the result... but I am unable to display which option the user has selected from the radiobutton.if you look at it in the browser, and type in a name in the name textbox and click submit....it displays the result (which was stored in the inputarray) but the radiobutton doesnt work...gives.."undefined" and should give either Male or Female, depending on what the user selects.

## Create An Associative Array Dynamically Pulling The Index Values From An Array (propertyArray)?

Mar 2, 2009

I want to create an associative array dynamically pulling the index values from an array (propertyArray); Associative array is created inside create function and then returned. But after it is returned, I cant use index names to retrieve values. It returns undefined as below code shows.

Code JavaScript:

var propertyArray=["a","b","c"];
function create(){
var array=[];

[code]....

## Return Array - C# Code - Connecting To Database And Creating A Array - List

Jan 21, 2011

Modifying my code:

I have this C# code that is connecting to database and creating a array(list)

Code:

I'm trying to pass it to a javascript function so I can then pass it to a silverlight page so I was able to create this easy javascript that show a aleart box on startup of the list(array)

Code:

But I want to do something like this and can't get it:

Code:

## JQuery :: Submenu From Array - Function ToggleOptions Takes 3 Variables - Target - Array - State

Feb 15, 2011

I am trying to understand somecode. I don't think I am understanding everything correctly. Can someone confirm or add to my understanding?

Here is the code, below is my explanation:

- CODE 1 - is saying if the the class subnav_dd is called on an anchor tag on a li, then make the function in the if statement "live". (Live in a sense binds the function to the condition, but unlike bind it allows the condition to be used more then once. ) So if the class subnav_dd is the parent, and has a class of .dis then prevent anything below it from firing. CSS - If code 1 is true, then I will only get the first li to fire, the remaining ones will not.

- CODE 2 - This one is a little tricky. Function ToggleOptions takes 3 variables (target, array, state). The condition is if the div subnav + target have siblings, then check to see how many siblings are there. Put the amount of siblings into an array, then check the state of each sibling. I don't completely the rest of it.

I think if the div subnav is called and something is found in the array then the class dis is either added or removed. Then what? I don't understand why I still need the else that adds a class to #subnav_ +.target

## Correct Syntax For An Nested Array Where Each Array Element Has 3 Elements, A Number And Two Text Strings?

Sep 17, 2010

What is the correct syntax for an nested array where each array element has 3 elements, a number and two text strings?

Code:

array = ['1, Old Man, Old Man','2 Black Sheep, Black Sheep',....]

should the text strings be in double quotes("")?

Code:

array = ['1, "Old Man", "Old Man"','2 "Black Sheep", "Black Sheep"',....]

## Sorting Objects Inside Of Multidiminsional Array For Main Array?

Apr 25, 2011

I am really hoping someone is willing to take the time to read this post and take a minute to take a look at my code. What is happening is there are some matches for a script I made and then an area for segments during an event. If you notice on the segment part of the form is that there is a dropdown that asks for where in the event that segment needs to go. With the Introduction or the different numbered matches. What I need to happen for a subArray I need it to take the introduction, all the matches, and all the segments and order them accordingly. With the introduction first, the matches in order based off there match number and then the segments in between the introduction or matches based off the user's input.[URL]..

## Convert Php Array To Array And Populate Form Text Fields

Nov 3, 2010

I am working on a page where the user will select a location from a dynamically generated dropdown list. I was able to create the php multidimensional array (tested and working) from a MySql database using the users information at login, but I'm having problems converting it to a javascript multidimensional array. I need to be able to access variables that I can pass to a number of text fields within an html form.For instance, if a user belongs to a company with multiple addresses, I need to be able to let them select the address they need to prepopulate specific text fields.

## Comparing Array Values To Select Unique Array Elements?

Apr 10, 2010

This one is throwing me off! Either I am making a stupid mistake or I'm doing it totally wrong I have an array, and I am trying to select unique values from it and assign it to another array. Here is the code:

Code:
var flag;
for (i=0;i<=pdfs.length-1;i++)
{
flag = 1;
for (j=0;j<=pdfs2.length-1;j++)

[Code]...

The problem is that the if (pdfs2[j] == pdfs[i]) statement ends up never being true. There are URL's to pdf files in the array. On the other side, if there is a much easier way to select unique values from an array, please feel free to point it out.

## Prototype To Sort An Associative Array On The Array Key (in Ascending Order)

Sep 1, 2010

I am building a customised javascript prototype to sort an associative array on the array key (in ascending order). Basically, I am separating the array keys into a separate array and then using .sort() to sort the keys and then reassembling the original associative array elements according to the sorted keys array.

The sorting works ok except that when I run the test code below, the outputed sorted associative array has an extra element at the end of the array whose key is the name of the prototype function and the value for that element is the function code itself. Obviously I am misunderstanding something about associative arrays or how javascript prototypes work.

[Code]...

## Auto-suggest Array Search - From The Data Stored In Array

Nov 19, 2011

I want to have a simple code such that some data is stored in array. When we create a search box it has to give suggestions from the data stored in array.

## Shuffle Array Elements (3 To End Of Array) In Random Order

May 6, 2007

I'd like to reorganize the third, fourth, fifth and sixth, as well as any
elements thereafter in an array in random order:

var a = new Array('first','second','third','fourth','fifth','s ixth','etc')

In other words, the first, second and third element should remain in
position 0, 1 and 2, while the fourth, fifth and sixth, etc. should appear
in random order.

## Take Data From An Array And Apply Each Array Item To An Element

Mar 26, 2010

I'm trying to grab values from a set of arrays based on the value returned by my select box.

**Caveat - this is not an area I have any real experience with**

My arrays look like:

Code JavaScript:

I then need to test for each, then associate with one of my fees arrays, then grab each of the values in the array and write those values to elements within my page.

I'm then doing this to evaluate for each degree

Code JavaScript:

I need to first figure out how best to import all of these 60+ arrays and then in each of my conditions pull out each value and write to my page.

There is a unique 1 to 1 relationship between each degree and array so I can't consolidate as the values for each degree differ slightly.

## Array - Value Of A Variable To Perform Multiplication Against Array

Mar 20, 2009

I am accepting an array, and a value of a variable to perform multiplication against my array, then write the product back into the array.

[Code]...