Both Array and Vector have some methods that allow AS3 programmers to do some functional programming: every, filter, forEach, map, and some. These can lead to flexible and concise code, but at what performance cost? Today I’ll test them to get a handle on just how much speed you’re giving away by using these methods.
Posts Tagged arrays
Declaring Vectors
Jun 14
The differences between Vector and Array have been quite interesting since Vector was introduced in Flash Player 10. Until just recently I didn’t know that there was special syntax for declaring a Vector akin to Array's special a = [1,2,3,4,5] trick. This got me thinking about the various ways one can declare a Vector and, of course, how they’re implemented in bytecode and what the speed differences, if any, are. Read on for some nitty gritty about how you declare Vectors in AS3.
Linked Lists: Part 3
Dec 23
Linked Lists: Part 2
Dec 21
Last time I began covering linked lists in AS3. As anyone who has ever taken a data structures class can tell you, this is definitely a core data structure. As such, it has numerous benefits compared to other single-dimensional data structures like arrays and hash tables. The Array class in AS3 is far from a C/C++ array, which is simply a contiguous block of memory. AS3′s Array class blurs the lines between arrays, linked lists, and hash tables. So as I implement a linked list class in AS3 it is quite interesting to see how the normal pros and cons change. I’ve expanded on the LinkedList class I started last week and done some more preliminary performance testing. Read on to see the updates.
Linked Lists: Part I
Dec 18
I’ve written before about linked lists when I covered free lists. There were massive speedups to be had there, but that article mostly covered the performance costs of allocation and deallocation. Today is part one of a series that more generally covers linked lists.
Array Performance
Dec 14
Today’s article is inspired by Jean-Philippe Auclair’s excellent article on arrays and the comment he recently posted on my article about map performance. In it he discusses how the Array class is implemented using a densely-packed C/C++ array (a contiguous block of memory) and, after the first undefined element, a hash table. This got me thinking of three questions, together the subject of today’s article. First, when an Array‘s densely-packed portion is split using the delete operator, how fast is this? Secondly, can it be re-joined? Third, how fast is rejoining it?
Map Performance
Nov 23
I recently received an e-mail from Dmitry Zhelnin (translation) with a test he did concerning the speed of a couple ways to get a value for a key, which I like to call a map and Wikipedia likes to call an associative array. I’d been meaning to do a similar test for a while now and, guess what, I finally have! UPDATE: fixed miss test for fixed-size Vectors.
Loop Speed
Oct 7
AS3 gives you a good number of potential ways you can loop over collections. When Flash Player 10 first came out, I went ahead and tested out the new Vector class in a variety of ways. One of them was to pit it against the collections available in Flash Player 9: Array, Object, Dictionary, ByteArray, and even BitmapData. Below I’ll show you my test and discuss its results.
Sorting Vectors
Sep 2
The Array class has a great function: sortOn(). It does a fast sort based on a property of each element of the array. Unfortunately, there is no equivalent in the Vector class. Below are some attempts to get around that limitation and preserve as much of the speed of sortOn() as possible.
Adding to Arrays and Vectors
Aug 31
Adding on to existing arrays and vectors is one of those really common tasks that sounds dreary. Everyone knows about push() and unshift() for single elements and concat() for lots of elements. But what if you want to add a lot of elements to an existing array or vector without allocating a new array or vector? I have the solution.
