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  • Make Div overlay ENTIRE page (not just viewport)??

    - by Polaris878
    Hello, So I have a problem that I think is quite common but I have yet to find a good solution for. I want to make an overlay div cover the ENTIRE page... NOT just the viewport. I don't understand why this is so hard to do... I've tried setting body, html heights to 100% etc but that isn't working. Here is what I have so far: <html> <head> <style type="text/css"> .OverLay { position: absolute; z-index: 3; opacity: 0.5; filter: alpha(opacity = 50); top: 0; bottom: 0; left: 0; right: 0; width: 100%; height: 100%; background-color: Black; color: White;} body { height: 100%; } html { height: 100%; } </style> </head> <body> <div style="height: 100%; width: 100%; position: relative;"> <div style="height: 100px; width: 300px; background-color: Red;"> </div> <div style="height: 230px; width: 9000px; background-color: Green;"> </div> <div style="height: 900px; width: 200px; background-color: Blue;"></div> <div class="OverLay">TestTest!</div> </div> </body> </html> I'd also be open to a solution in JavaScript if one exists, but I'd much rather just be using some simple CSS.

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  • Move options between multiple lists

    - by Martha
    We currently have a form with the standard multi-select functionality of "here are the available options, here are the selected options, here are some buttons to move stuff back and forth." However, the client now wants the ability to not just select certain items, but to also categorize them. For example, given a list of books, they want to not just select the ones they own, but also the ones they've read, the ones they would like to read, and the ones they've heard about. (All examples fictional.) Thankfully, a selected item can only be in one category at a time. I can find many examples of moving items between listboxes, but not a single one for moving items between multiple listboxes. To add to the complication, the form needs to have two sets of list+categories, e.g. a list of movies that need to be categorized in addition to the aforementioned books. EDIT: Having now actually sat down to try to code the non-javascripty bits, I need to revise my question, because I realized that multiple select lists won't really work from the "how do I inform the server about all this lovely new information" standpoint. So the html code is now a pseudo-listbox, i.e. an unordered list (ul) displayed in a box with a scrollbar, and each list item (<li>) has a set of five radio buttons (unselected/own/read/like/heard). My task is still roughly the same: how to take this one list and make it easy to categorize the items, in such a way that the user can tell at a glance what is in what category. (The pseudo-listbox has some of the same disadvantages as a multi-select listbox, namely it's hard to tell what's selected if the list is long enough to scroll.) The dream solution would be a drag-and-drop type thing, but at this point even buttons would be OK. Another modification (a good one) is that the client has revised the lists, so the longest is now "only" 62 items long (instead of the many hundreds they had before). The categories will still mostly contain zero, one, or two selected items, possibly a couple more if the user was overzealous. As far as OS and stuff, the site is in classic asp (quit snickering!), the server-side code is VBScript, and so far we've avoided the various Javascript libraries by the simple expedient of almost never using client-side scripting. This one form for this one client is currently the big exception. Give 'em an inch and they want a mile... Oh, and I have to add: I suck at Javascript, or really at any C-descendant language. Curly braces give me hives. I'd really, really like something I can just copy & paste into my page, maybe tweak some variable names, and never look at it again. A girl can dream, can't she? :) [existing code deleted because it's largely irrelevant.]

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  • Issues accessing an object's array values - returns null or 0s

    - by PhatNinja
    The function below should return an array of objects with this structure: TopicFrequency = { name: "Chemistry", //This is dependent on topic data: [1,2,3,4,5,6,7,8,9,10,11,12] //This would be real data }; so when I do this: myData = this.getChartData("line"); it should return two objects: {name : "Chemistry", data : [1,2,3,4,51,12,0,0, 2,1,41, 31]} {name : "Math", data : [0,0,41,4,51,12,0,0, 2,1,41, 90]} so when I do console.log(myData); it's perfect, returns exactly this. However when I do console.log(myData[0].data) it returns all 0s, not the values. I'm not sure what this issues is known as, and my question is simple what is this problem known as? Here is the full function. Somethings were hardcoded and other variables (notable server and queryContent) removed. Those parts worked fine, it is only when manipulated/retreiving the returned array's values that I run into problems. Note this is async. so not sure if that is also part of the problem. getChartData: function (chartType) { var TopicsFrequencyArray = new Array(); timePairs = this.newIntervalSet("Month"); topicList = new Array("Chemistry", "Math");//Hard coded for now var queryCopy = { //sensitive information }; for (i = 0; i < topicList.length; i++) { var TopicFrequency = { name: null, data: this.newFilledArray(12, 0) }; j = 0; TopicFrequency.name = topicList[i]; while (j < timePairs.length) { queryCopy.filter = TopicFrequency.name; //additional queryCopy parameter changes made here var request = esri.request({ url: server, content: queryCopy, handleAs: "json", load: sucess, error: fail }); j = j + 1; function sucess(response, io) { var topicCountData = 0; query = esri.urlToObject(io.url); var dateString = query.query.fromDate.replace("%", " "); dateString = dateString.replace(/-/g, "/"); dateString = dateString.split("."); date = new Date(dateString[0]); dojo.forEach(response.features, function (feature) { if (feature.properties.count > 0) { topicCountData = feature.properties.count; } TopicFrequency.data[date.getMonth()] = topicCountData; }); } function fail(error) { j = j + 1; alert("There was an unspecified error with this request"); console.log(error); } } TopicsFrequencyArray.push(TopicFrequency); } },

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  • HTML5 <audio> Safari live broadcast vs not

    - by Peter Parente
    I'm attempting to embed an HTML5 audio element pointing to MP3 or OGG data served by a PHP file . When I view the page in Safari, the controls appear, but the UI says "Live Broadcast." When I click play, the audio starts as expected. Once it ends, however, I can't start it playing again by clicking play. Even using the JS API on the audio element and setting currentTime to 0 fails with an index error exception. I suspected the headers from the PHP script were the problem, particularly missing a content length. But that's not the case. The response headers include a proper Content- Length to indicate the audio has finite size. Furthermore, everything works as expected in Firefox 3.5+. I can click play on the audio element multiple times to hear the sound replay. If I remove the PHP script from the equation and serve up a static copy of the MP3 file, everything works fine in Safari. Does this mean Safari is treating audio src URLs with query parameters differently than URLs that don't have them? Anyone have any luck getting this to work? My simple example page is: <!DOCTYPE html> <html> <head></head> <body> <audio controls autobuffer> <source src="say.php?text=this%20is%20a%20test&format=.ogg" /> <source src="say.php?text=this%20is%20a%20test&format=.mp3" /> </audio> </body> </html> HTTP Headers from PHP script: HTTP/1.x 200 OK Date: Sun, 03 Jan 2010 15:39:34 GMT Server: Apache X-Powered-By: PHP/5.2.10 Content-Length: 8993 Keep-Alive: timeout=2, max=98 Connection: Keep-Alive Content-Type: audio/mpeg HTTP Headers from direct file access: HTTP/1.x 200 OK Date: Sun, 03 Jan 2010 20:06:59 GMT Server: Apache Last-Modified: Sun, 03 Jan 2010 03:20:02 GMT Etag: "a404b-c3f-47c3a14937c80" Accept-Ranges: bytes Content-Length: 8993 Keep-Alive: timeout=2, max=100 Connection: Keep-Alive Content-Type: audio/mpeg I tried hard-coding the Accept-Ranges header into the script too, but no luck.

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  • CI pagination, POST problem

    - by Gwood
    Okay, I am pretty new in CI and I am stuck on pagination. I am performing this pagination on a record set that is result of a query. Now everything seems to be working fine. But there’s some problem probably with the link. I am displaying 10 results per page. Now if the results are less than 10 then it’s fine. Or If I pull up the entire records in the table it works fine. But in case the result is more than 10 rows, then the first 10 is perfectly displayed, and when I click on the pagination link to get to the next page the next page displays the rest of the results from the query as well as, other records in the table. ??? I am confused.. Any help?? Here’s the model code I am using .... function getTeesLike($field,$param) { $this-db-like($field,$param); $this-db-limit(10, $this-uri-segment(3)); $query=$this-db-get(‘shirt’); if($query-num_rows()0){ return $query-result_array(); } } function getNumTeesfromQ($field,$param) { $this-db-like($field,$param); $query=$this-db-get(‘shirt’); return $query-num_rows(); } And here’s the controller code .... $KW=$this-input-post(‘searchstr’); $this-load-library(‘pagination’); $config[‘base_url’]=‘http://localhost/cit/index.php/tees/show/’; $config[‘total_rows’]=$this-T-getNumTeesfromQ(‘Title’,$KW); $config[‘per_page’]=‘10’; $this-pagination-initialize($config); $data[‘tees’]=$this-T-getTeesLike(‘Title’,$KW); $data[‘title’]=‘Displaying Tees data’; $data[‘header’]=‘Tees List’; $data[‘links’]=$this-pagination-create_links(); $this-load-view(‘tee_res’, $data); //What am I doing wrong here ???? Pls help ... I guess the problem is with the $KW=$this-input-post(‘searchstr’); .. Because if I hard code a value for $KW it works fine. May be I should use POST differently ..but how do I pass the value from the form without POSTING it , its CI so not GET ... ??????

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  • jQuery: resizing element cuts off parent's background

    - by Justine
    Hi, I've been trying to recreate an effect from this tutorial: http://jqueryfordesigners.com/jquery-look-tim-van-damme/ Unfortunately, I want a background image underneath and because of the resize going on in JavaScript, it gets resized and cut off as well, like so: http://dev.gentlecode.net/dotme/index-sample.html - you can view source there to check the HTML, but basic structure looks like this: <div class="page"> <div class="container"> div.header ul.nav div.main </div> </div> Here is my jQuery code: $('ul.nav').each(function() { var $links = $(this).find('a'), panelIds = $links.map(function() { return this.hash; }).get().join(","), $panels = $(panelIds), $panelWrapper = $panels.filter(':first').parent(), delay = 500; $panels.hide(); $links.click(function() { var $link = $(this), link = (this); if ($link.is('.current')) { return; } $links.removeClass('current'); $link.addClass('current'); $panels.animate({ opacity : 0 }, delay); $panelWrapper.animate({ height: 0 }, delay, function() { var height = $panels.hide().filter(link.hash).show().css('opacity', 1).outerHeight(); $panelWrapper.animate({ height: height }, delay); }); }); var showtab = window.location.hash ? '[hash=' + window.location.hash + ']' : ':first'; $links.filter(showtab).click(); }); In this example, panelWrapper is a div.main and it gets resized to fit the content of tabs. The background is applied to the div.page but because its child is getting resized, it resizes as well, cutting off the background image. It's hard to explain so please look at the link above to see what I mean. I guess what I'm trying to ask is: is there a way to resize an element without resizing its parent? I tried setting height and min-height of .page to 100% and 101% but that didn't work. I tried making the background image fixed, but nada. It also happens if I add the background to the body or even html. Help?

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  • Reading and writing C++ vector to a file

    - by JB
    For some graphics work I need to read in a large amount of data as quickly as possible and would ideally like to directly read and write the data structures to disk. Basically I have a load of 3d models in various file formats which take too long to load so I want to write them out in their "prepared" format as a cache that will load much faster on subsequent runs of the program. Is it safe to do it like this? My worries are around directly reading into the data of the vector? I've removed error checking, hard coded 4 as the size of the int and so on so that i can give a short working example, I know it's bad code, my question really is if it is safe in c++ to read a whole array of structures directly into a vector like this? I believe it to be so, but c++ has so many traps and undefined behavour when you start going low level and dealing directly with raw memory like this. I realise that number formats and sizes may change across platforms and compilers but this will only even be read and written by the same compiler program to cache data that may be needed on a later run of the same program. #include <fstream> #include <vector> using namespace std; struct Vertex { float x, y, z; }; typedef vector<Vertex> VertexList; int main() { // Create a list for testing VertexList list; Vertex v1 = {1.0f, 2.0f, 3.0f}; list.push_back(v1); Vertex v2 = {2.0f, 100.0f, 3.0f}; list.push_back(v2); Vertex v3 = {3.0f, 200.0f, 3.0f}; list.push_back(v3); Vertex v4 = {4.0f, 300.0f, 3.0f}; list.push_back(v4); // Write out a list to a disk file ofstream os ("data.dat", ios::binary); int size1 = list.size(); os.write((const char*)&size1, 4); os.write((const char*)&list[0], size1 * sizeof(Vertex)); os.close(); // Read it back in VertexList list2; ifstream is("data.dat", ios::binary); int size2; is.read((char*)&size2, 4); list2.resize(size2); // Is it safe to read a whole array of structures directly into the vector? is.read((char*)&list2[0], size2 * sizeof(Vertex)); }

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  • Learn C# now or finish up with Java and then learn C#?

    - by Sahat
    Ok here is my situation. I've studied Java in my college for 2 semesters. But you know they teach you jack in there, just the basics. We skipped half of our textbook and even then our professors don't teach from section to section of each chapter. I don't blame them. It's hard as it is for new students to understand even the basic concepts of programming. Now this is a community college we are talking about and not Stanford, MIT or Berkeley. So like I said I've done 2 semester of Java. I really like our textbook because it has some challenging projects to do at the end of each chapter. This textbook is pretty clear and i have no problem understanding it (although 2-D and 3-D Arrays have given me some trouble). I have tried reading a few C# books such as Pro C# 2008 and .NET 3.5 and C# 4.0 in a Nutshell. I found these books to be dry and overloaded with information that put me to sleep (No offense to the authors of those 2 wonderful, according to amazon ratings, books). Would you suggest I finish my Java textbook, brush up my knowledge of Arrays, Polymorphism, and etc that are universal to most programming languages. And then switch to C#, plus the syntax is very similar so it should be easy to switch. Or should I just start learning C# right now from the very beginning? If it's the latter then could you recommend some free online resources that will keep me engaged and at the same time teach me everything I need to know about C#. Someone has recommended me to learn .NET first, but I found it to be not the brightest idea. .NET is just a big monster full of libraries. How am I going to apply it if I don't even know the C# or VB!? Anyway back to my question: Master Java and switch to C# or just go with C#? DISCLAIMER: I don't want to start .NET vs J2EE or C# vs Java flame war. I am going with C#. I've decided that I want to work in a Microsoft shop in the future. .NET is what I want to learn. Thanks! Will be waiting for the answers.

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  • Rails 3 NameError (cannot remove Object::Version) error

    - by Jeff D
    Can anyone point me at what might be causing this error? There is no ApplicationTrace, and it locks the server hard on my development machine. I think it has something to do with the way rails reloads your classes in development mode, and it appears to have something to do with a Version constant. I can't find a reference to this though. Can anyone point me in the direction of what would cause this? activesupport (3.0.3) lib/active_support/dependencies.rb:645:in `remove_const' activesupport (3.0.3) lib/active_support/dependencies.rb:645:in `remove_constant' activesupport (3.0.3) lib/active_support/dependencies.rb:645:in `instance_eval' activesupport (3.0.3) lib/active_support/dependencies.rb:645:in `remove_constant' activesupport (3.0.3) lib/active_support/dependencies.rb:521:in `remove_unloadable_constants!' activesupport (3.0.3) lib/active_support/dependencies.rb:521:in `each' activesupport (3.0.3) lib/active_support/dependencies.rb:521:in `remove_unloadable_constants!' activesupport (3.0.3) lib/active_support/dependencies.rb:317:in `clear' railties (3.0.3) lib/rails/application/bootstrap.rb:60:in `_callback_after_7' activesupport (3.0.3) lib/active_support/callbacks.rb:419:in `_run_call_callbacks' actionpack (3.0.3) lib/action_dispatch/middleware/callbacks.rb:44:in `call' rack (1.2.1) lib/rack/sendfile.rb:107:in `call' actionpack (3.0.3) lib/action_dispatch/middleware/remote_ip.rb:48:in `call' actionpack (3.0.3) lib/action_dispatch/middleware/show_exceptions.rb:46:in `call' railties (3.0.3) lib/rails/rack/logger.rb:13:in `call' rack (1.2.1) lib/rack/runtime.rb:17:in `call' activesupport (3.0.3) lib/active_support/cache/strategy/local_cache.rb:72:in `call' rack (1.2.1) lib/rack/lock.rb:11:in `call' rack (1.2.1) lib/rack/lock.rb:11:in `synchronize' rack (1.2.1) lib/rack/lock.rb:11:in `call' actionpack (3.0.3) lib/action_dispatch/middleware/static.rb:30:in `call' railties (3.0.3) lib/rails/application.rb:168:in `call' railties (3.0.3) lib/rails/application.rb:77:in `send' railties (3.0.3) lib/rails/application.rb:77:in `method_missing' railties (3.0.3) lib/rails/rack/log_tailer.rb:14:in `call' rack (1.2.1) lib/rack/content_length.rb:13:in `call' rack (1.2.1) lib/rack/handler/webrick.rb:52:in `service' /Volumes/files/jeffdeville/.rvm/rubies/ree-1.8.7-2010.02/lib/ruby/1.8/webrick/httpserver.rb:104:in `service' /Volumes/files/jeffdeville/.rvm/rubies/ree-1.8.7-2010.02/lib/ruby/1.8/webrick/httpserver.rb:65:in `run' /Volumes/files/jeffdeville/.rvm/rubies/ree-1.8.7-2010.02/lib/ruby/1.8/webrick/server.rb:173:in `start_thread' /Volumes/files/jeffdeville/.rvm/rubies/ree-1.8.7-2010.02/lib/ruby/1.8/webrick/server.rb:162:in `start' /Volumes/files/jeffdeville/.rvm/rubies/ree-1.8.7-2010.02/lib/ruby/1.8/webrick/server.rb:162:in `start_thread' /Volumes/files/jeffdeville/.rvm/rubies/ree-1.8.7-2010.02/lib/ruby/1.8/webrick/server.rb:95:in `start' /Volumes/files/jeffdeville/.rvm/rubies/ree-1.8.7-2010.02/lib/ruby/1.8/webrick/server.rb:92:in `each' /Volumes/files/jeffdeville/.rvm/rubies/ree-1.8.7-2010.02/lib/ruby/1.8/webrick/server.rb:92:in `start' /Volumes/files/jeffdeville/.rvm/rubies/ree-1.8.7-2010.02/lib/ruby/1.8/webrick/server.rb:23:in `start' /Volumes/files/jeffdeville/.rvm/rubies/ree-1.8.7-2010.02/lib/ruby/1.8/webrick/server.rb:82:in `start' rack (1.2.1) lib/rack/handler/webrick.rb:13:in `run' rack (1.2.1) lib/rack/server.rb:213:in `start' railties (3.0.3) lib/rails/commands/server.rb:65:in `start' railties (3.0.3) lib/rails/commands.rb:30 railties (3.0.3) lib/rails/commands.rb:27:in `tap' railties (3.0.3) lib/rails/commands.rb:27 script/rails:6:in `require' script/rails:6

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  • Gotchas INSERTing into SQLite on Android?

    - by paul.meier
    Hi friends, I'm trying to set up a simple SQLite database in Android, handling the schema via a subclass of SQLiteOpenHelper. However, when I query my tables, the columns I think I've inserted are never present. Namely, in SQLiteOpenHelper's onCreate(SQLiteDatabase db) method, I use db.execSQL() to run CREATE TABLE commands, then have tried both db.execSQL and db.insert() to run INSERT commands on the tables I've just created. This appears to run fine, but when I try to query them I always get 0 rows returned (for debugging, the queries I'm running are simple SELECT * FROM table and checking the Cursor's getCount()). Anybody run into anything like this before? These commands seem to run on command-line sqlite3. Are they're gotchas that I'm missing (e.g. INSERTS must/must not be semicolon terminated, or some issue involving multiple tables)? I've attached some of the code below. Thanks for your time, and let me know if I can clarify further. @Override public void onCreate(SQLiteDatabase db) { db.execSQL("CREATE TABLE "+ LEVEL_TABLE +" (" + " "+ _ID +" INTEGER PRIMARY KEY AUTOINCREMENT," + " level TEXT NOT NULL,"+ " rows INTEGER NOT NULL,"+ " cols INTEGER NOT NULL);"); db.execSQL("CREATE TABLE "+ DYNAMICS_TABLE +" (" + " level_id INTEGER NOT NULL," + " row INTEGER NOT NULL,"+ " col INTEGER NOT NULL,"+ " type INTEGER NOT NULL);"); db.execSQL("CREATE TABLE "+ SCORE_TABLE +" (" + " level_id INTEGER NOT NULL," + " score INTEGER NOT NULL,"+ " date_achieved DATE NOT NULL,"+ " name TEXT NOT NULL);"); this.enterFirstLevel(db); } And a sample of the insert code I'm currently using, which gets called in enterFirstLevel() (some values hard-coded just to get it running...): private void insertDynamic(SQLiteDatabase db, int row, int col, int type) { ContentValues values = new ContentValues(); values.put("level_id", "1"); values.put("row", Integer.toString(row)); values.put("col", Integer.toString(col)); values.put("type", Integer.toString(type)); db.insertOrThrow(DYNAMICS_TABLE, "col", values); } Finally, query code looks like this: private Cursor fetchLevelDynamics(int id) { SQLiteDatabase db = this.leveldata.getReadableDatabase(); try { String fetchQuery = "SELECT * FROM " + DYNAMICS_TABLE; String[] queryArgs = new String[0]; Cursor cursor = db.rawQuery(fetchQuery, queryArgs); Activity activity = (Activity) this.context; activity.startManagingCursor(cursor); return cursor; } finally { db.close(); } }

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  • Migrating from hand-written persistence layer to ORM

    - by Sergey Mikhanov
    Hi community, We are currently evaluating options for migrating from hand-written persistence layer to ORM. We have a bunch of legacy persistent objects (~200), that implement simple interface like this: interface JDBC { public long getId(); public void setId(long id); public void retrieve(); public void setDataSource(DataSource ds); } When retrieve() is called, object populates itself by issuing handwritten SQL queries to the connection provided using the ID it received in the setter (this usually is the only parameter to the query). It manages its statements, result sets, etc itself. Some of the objects have special flavors of retrive() method, like retrieveByName(), in this case a different SQL is issued. Queries could be quite complex, we often join several tables to populate the sets representing relations to other objects, sometimes join queries are issued on-demand in the specific getter (lazy loading). So basically, we have implemented most of the ORM's functionality manually. The reason for that was performance. We have very strong requirements for speed, and back in 2005 (when this code was written) performance tests has shown that none of mainstream ORMs were that fast as hand-written SQL. The problems we are facing now that make us think of ORM are: Most of the paths in this code are well-tested and are stable. However, some rarely-used code is prone to result set and connection leaks that are very hard to detect We are currently squeezing some additional performance by adding caching to our persistence layer and it's a huge pain to maintain the cached objects manually in this setup Support of this code when DB schema changes is a big problem. I am looking for an advice on what could be the best alternative for us. As far as I know, ORMs has advanced in last 5 years, so it might be that now there's one that offers an acceptable performance. As I see this issue, we need to address those points: Find some way to reuse at least some of the written SQL to express mappings Have the possibility to issue native SQL queries without the necessity to manually decompose their results (i.e. avoid manual rs.getInt(42) as they are very sensitive to schema changes) Add a non-intrusive caching layer Keep the performance figures. Is there any ORM framework you could recommend with regards to that?

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  • How do I add "Press any key to boot from usb" when installing Windows from a flash drive? (Grub4dos question / how to remove a bootloader)

    - by Vincent
    Hi there! I've been struggling with this problem for a while now and finially decided to ask for help. Let me first explain what the main purpose of the app is: to provide the a very easy to use way of backing up files, after which I format the drive and start Windows 7 setup. I do this by booting WinPE, which runs a script to detect Windows installations and then opens a file browser. After the file browser is closed, the script continues and formats the drive that contains the Windows installation, and starts an unattended Windows 7 install. Now here is the problem: When you start Windows setup or WinPE from a dvd, you get a nice option to "Press any key to boot from DVD". This is to prevent the computer from booting the DVD when the first phase of the installation is complete and the computer reboots. However, when booting from a flash drive, Windows does not provide this option: it simply boots the flash drive every reboot. To replicate the "press any key" function, I installed Grub4Dos, which works great. It provides a small menu, the first standard item being "Continue installation", the second being "start installation". After quite a lot of tweaking, I got everything working: Start installation starts WinPE, which in turn starts the Windows installation. At first reboot, the Grub4Dos menu comes up, counts 5 seconds and boots the second stage of the installation. Here, I am greeted with the error: "Windows setup could not configure windows to run on this computer's hardware." When I boot into WinPE the normal way (put the bootmgr on the stick root) and change my bios to boot from the primary hdd after first reboot, I don't get this error. I've been looking around, and the only thing I could find was that the BIOS automatically names the boot device hd0, and that Windows can only be run / installed to hd 0. I'm not sure if this is the problem. I read about remapping to solve this problem, but to do that you have to know the phisical location of the hard drive and partition, like hd(0,1). I want this flash drive to work on any PC, regardless of where the OS is installed, so that's not really a possibility. A possible fix I thought of is removing the bootloader from the flash drive when I'm in WinPE. That way, when the pc reboots the BIOS will not see the flash drive as a boot drive and instead boot the primary hdd. I have yet to find a way to do this. Thank you for reading my question, and if you have any suggestion, please do.

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  • How to get started with testing(jMock)

    - by London
    Hello, I'm trying to learn how to write tests. I'm also learning Java, I was told I should learn/use/practice jMock, I've found some articles online that help to certain extend like : http://www.theserverside.com/news/1365050/Using-JMock-in-Test-Driven-Development http://jeantessier.com/SoftwareEngineering/Mocking.html#jMock And most articles I found was about test driven development, write tests first then write code to make the test pass. I'm not looking for that at the moment, I'm trying to write tests for already existing code with jMock. The official documentation is vague to say the least and just too hard for me. Does anybody have better way to learn this. Good books/links/tutorials would help me a lot. thank you EDIT - more concrete question : http://jeantessier.com/SoftwareEngineering/Mocking.html#jMock - from this article Tried this to mock this simple class : import java.util.Map; public class Cache { private Map<Integer, String> underlyingStorage; public Cache(Map<Integer, String> underlyingStorage) { this.underlyingStorage = underlyingStorage; } public String get(int key) { return underlyingStorage.get(key); } public void add(int key, String value) { underlyingStorage.put(key, value); } public void remove(int key) { underlyingStorage.remove(key); } public int size() { return underlyingStorage.size(); } public void clear() { underlyingStorage.clear(); } } Here is how I tried to create a test/mock : public class CacheTest extends TestCase { private Mockery context; private Map mockMap; private Cache cache; @Override @Before public void setUp() { context = new Mockery() { { setImposteriser(ClassImposteriser.INSTANCE); } }; mockMap = context.mock(Map.class); cache = new Cache(mockMap); } public void testCache() { context.checking(new Expectations() {{ atLeast(1).of(mockMap).size(); will(returnValue(int.class)); }}); } } It passes the test and basically does nothing, what I wanted is to create a map and check its size, and you know work some variations try to get a grip on this. Understand better trough examples, what else could I test here or any other exercises would help me a lot. tnx

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  • Poor man's "lexer" for C#

    - by Paul Hollingsworth
    I'm trying to write a very simple parser in C#. I need a lexer -- something that lets me associate regular expressions with tokens, so it reads in regexs and gives me back symbols. It seems like I ought to be able to use Regex to do the actual heavy lifting, but I can't see an easy way to do it. For one thing, Regex only seems to work on strings, not streams (why is that!?!?). Basically, I want an implementation of the following interface: interface ILexer : IDisposable { /// <summary> /// Return true if there are more tokens to read /// </summary> bool HasMoreTokens { get; } /// <summary> /// The actual contents that matched the token /// </summary> string TokenContents { get; } /// <summary> /// The particular token in "tokenDefinitions" that was matched (e.g. "STRING", "NUMBER", "OPEN PARENS", "CLOSE PARENS" /// </summary> object Token { get; } /// <summary> /// Move to the next token /// </summary> void Next(); } interface ILexerFactory { /// <summary> /// Create a Lexer for converting a stream of characters into tokens /// </summary> /// <param name="reader">TextReader that supplies the underlying stream</param> /// <param name="tokenDefinitions">A dictionary from regular expressions to their "token identifers"</param> /// <returns>The lexer</returns> ILexer CreateLexer(TextReader reader, IDictionary<string, object> tokenDefinitions); } So, pluz send the codz... No, seriously, I am about to start writing an implementation of the above interface yet I find it hard to believe that there isn't some simple way of doing this in .NET (2.0) already. So, any suggestions for a simple way to do the above? (Also, I don't want any "code generators". Performance is not important for this thing and I don't want to introduce any complexity into the build process.)

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  • Ajax problem after deleting a div, then creating a new one

    - by Matt Nathanson
    I'm building a custom CMS where you can add and delete clients using ajax and jquery 1.4.2. My problem lies after I delete a div. The ajax is used to complete this and refresh automatically.. But when I go to create a new div (without a hard refresh) it puts it back in the slot of the div I just deleted. How can I get this to completely forget about the div i just deleted and place the new div in the next database table? link for reference: http://staging.sneakattackmedia.com/cms/ //Add New client // function AddNewClient() { dataToLoad = 'addClient=yes'; $.ajax({ type: 'post', url: '/clients/controller.php', datatype: 'html', data: dataToLoad, target: ('#clientssidebar'), async: false, success: function(html){ $(this).click(function() {reInitialize()}); //$('#clientssidebar').html(html); $('div#' + clientID).slideDown(800); $(this).click(function() { ExpandSidebar()});}, error: function() { alert('An error occured! 222');} });}; //Delete Client // function DeleteClient(){ var yes = confirm("Whoa there chief! Do you really want to DELETE this client?"); if (yes == 1) { dataToLoad = 'clientID=' + clientID + '&deleteClient=yes', $.ajax({ type: 'post', url: '/clients/controller.php', datatype: 'html', data: dataToLoad, success: function(html) { alert('Client' + clientID + ' should have been deleted from the database.'); $(this).click(function() {reInitialize()}); $('div#' +clientID).slideUp(800); }, error: function() { alert('error'); }});};}; //Re Initialize // function reInitialize() { $('#addnew').click(function() {AddNewClient()}); $('.deletebutton').click(function() {clientID = $(this).parent().attr('id'); DeleteClient()}) $('.clientblock').click(function() {clientID = $(this).attr('id'); ExpandSidebar()});}; //Document Ready // $(document).ready(function(){ if ($('isCMS')){ editCMS = 1; $('.deletebutton').click(function() {clientID = $(this).parent().attr('id'); DeleteClient()}); $('#addnew').click(function() {AddNewClient()}); $('.clientblock').click(function() {clientID = $(this).attr('id'); ExpandSidebar()}); $('.clientblock').click(function() {if (clickClient ==true) { $(this).css('background-image', 'url(/images/highlightclient.png)'); $(this).css('margin-left' , '30px'); }; $(this).click(function(){ $(this).css('background-image', ''); }); $('.uploadbutton').click(function(){UploadThings()}); }); } else ($('#clientscontainer')) { $('#editbutton').css('display', 'none'); }; }); Please help!!!

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  • IEnumerable<T> ToArray usage, is it a copy or a pointer?

    - by Daniel
    I am parsing an arbitrary length byte array that is going to be passed around to a few different layers of parsing. Each parser creates a Header and a Packet payload just like any ordinary encapsulation. And my problem lies in how the encapsulation holds its packet byte array payload. Say i have a 100 byte array, and it has 3 levels of encapsulation. 3 packet objects will be created and i want to set the payload of these packets to the corresponding position in the byte array of the packet. For example lets say the payload size is 20 for all levels, then imagine it has a public byte[] Payload on each object. However the problem is that this byte[] Payload is a copy of the original 100 bytes. So i'm going to end up with 160 bytes in memory instead of 100. If it were in c++ i could just easily use a pointer however i'm writing this in c#. So i created the following class: public class PayloadSegment<T> : IEnumerable<T> { public readonly T[] Array; public readonly int Offset; public readonly int Count; public PayloadSegment(T[] array, int offset, int count) { this.Array = array; this.Offset = offset; this.Count = count; } public T this[int index] { get { if (index < 0 || index >= this.Count) throw new IndexOutOfRangeException(); else return Array[Offset + index]; } set { if (index < 0 || index >= this.Count) throw new IndexOutOfRangeException(); else Array[Offset + index] = value; } } public IEnumerator<T> GetEnumerator() { for (int i = Offset; i < Offset + Count; i++) yield return Array[i]; } System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator() { IEnumerator<T> enumerator = this.GetEnumerator(); while (enumerator.MoveNext()) { yield return enumerator.Current; } } } This way i can simply reference a position inside the original byte array but use positional indexing. However if i do something like: PayloadSegment<byte> something = new PayloadSegment<byte>(someArray, 5, 10); byte[] somethingArray = something.ToArray(); Will the somethingArray be a copy of the bytes, or a reference to the original PayloadSegment which in turn is a reference to the original byte array? Sorry it was hard to word this lol _<

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  • Is this a legitimate implementation of a 'remember me' function for my web app?

    - by user246114
    Hi, I'm trying to add a "remember me" feature to my web app to let a user stay logged in between browser restarts. I think I got the bulk of it. I'm using google app engine for the backend which lets me use java servlets. Here is some pseudo-code to demo: public class MyServlet { public void handleRequest() { if (getThreadLocalRequest().getSession().getAttribute("user") != null) { // User already has session running for them. } else { // No session, but check if they chose 'remember me' during // their initial login, if so we can have them 'auto log in' // now. Cookie[] cookies = getThreadLocalRequest().getCookies(); if (cookies.find("rememberMePlz").exists()) { // The value of this cookie is the cookie id, which is a // unique string that is in no way based upon the user's // name/email/id, and is hard to randomly generate. String cookieid = cookies.find("rememberMePlz").value(); // Get the user object associated with this cookie id from // the data store, would probably be a two-step process like: // // select * from cookies where cookieid = 'cookieid'; // select * from users where userid = 'userid fetched from above select'; User user = DataStore.getUserByCookieId(cookieid); if (user != null) { // Start session for them. getThreadLocalRequest().getSession() .setAttribute("user", user); } else { // Either couldn't find a matching cookie with the // supplied id, or maybe we expired the cookie on // our side or blocked it. } } } } } // On first login, if user wanted us to remember them, we'd generate // an instance of this object for them in the data store. We send the // cookieid value down to the client and they persist it on their side // in the "rememberMePlz" cookie. public class CookieLong { private String mCookieId; private String mUserId; private long mExpirationDate; } Alright, this all makes sense. The only frightening thing is what happens if someone finds out the value of the cookie? A malicious individual could set that cookie in their browser and access my site, and essentially be logged in as the user associated with it! On the same note, I guess this is why the cookie ids must be difficult to randomly generate, because a malicious user doesn't have to steal someone's cookie - they could just randomly assign cookie values and start logging in as whichever user happens to be associated with that cookie, if any, right? Scary stuff, I feel like I should at least include the username in the client cookie such that when it presents itself to the server, I won't auto-login unless the username+cookieid match in the DataStore. Any comments would be great, I'm new to this and trying to figure out a best practice. I'm not writing a site which contains any sensitive personal information, but I'd like to minimize any potential for abuse all the same, Thanks

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  • how to refactor user-permission system?

    - by John
    Sorry for lengthy question. I can't tell if this should be a programming question or a project management question. Any advice will help. I inherited a reasonably large web project (1 year old) from a solo freelancer who architected it then abandoned it. The project was a mess, but I cleaned up what I could, and now the system is more maintainable. I need suggestions on how to extend the user-permission system. As it is now, the database has a t_user table with the column t_user.membership_type. Currently, there are 4 membership types with the following properties: 3 of the membership types are almost functionally the same, except for the different monthly fees each must pay 1 of the membership type is a "fake-user" type which has limited access ( different business logic also applies) With regards to the fake-user type, if you look in the system's business logic files, you will see a lot of hard-coded IF statements that do something like if (fake-user) { // do something } else { // a paid member of type 1,2 or 3 // proceed normally } My client asked me to add 3 more membership types to the system, each of them with unique features to be implemented this month, and substantive "to-be-determined" features next month. My first reaction is that I need to refactor the user-permission system. But it concerns me that I don't have enough information on the "to-be-determined" membership type features for next month. Refactoring the user-permission system will take a substantive amount of time. I don't want to refactor something and throw it out the following month. I get substantive feature requests on a monthly basis that come out of the blue. There is no project road map. I've asked my client to provide me with a roadmap of what they intend to do with the new membership types, but their answer is along the lines of "We just want to do [feature here] this month. We'll think of something new next month." So questions that come to mind are: 1) Is it dangerous for me to refactor the user permission system not knowing what membership type features exist beyond a month from now? 2) Should I refactor the user permission system regardless? Or just continue adding IF statements as needed in all my controller files? Or can you recommend a different approach to user permission systems? Maybe role-based ? 3) Should this project have a road map? For a 1 year old project like mine, how far into the future should this roadmap project? 4) Any general advice on the best way to add 3 new membership types?

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  • Design patterns and interview question

    - by user160758
    When I was learning to code, I read up on the design patterns like a good boy. Long after this, I started to actually understand them. Design discussions such as those on this site constantly try to make the rules more and more general, which is good. But there is a line, over which it becomes over-analysis starts to feed off itself and as such I think begins to obfuscate the original point - for example the "What's Alternative to Singleton" post and the links contained therein. http://stackoverflow.com/questions/1300655/whats-alternative-to-singleton I say this having been asked in both interviews I’ve had over the last 2 weeks what a singleton is and what criticisms I have of it. I have used it a few times for items such as user data (simple key-value eg. last file opened by this user) and logging (very common i'm sure). I've never ever used it just to have what is essentially global application data, as this is clearly stupid. In the first interview, I reply that I have no criticisms of it. He seemed disappointed by this but as the job wasn’t really for me, I forgot about it. In the next one, I was asked again and, as I wanted this job, I thought about it on the spot and made some objections, similar to those contained in the post linked to above (I suggested use of a factory or dependency injection instead). He seemed happy with this. But my problem is that I have used the singleton without ever using it in this kind of stupid way, which I had to describe on the spot. Using it for global data and the like isn’t something I did then realised was stupid, or read was stupid so didn’t do, it was just something I knew was stupid from the start. Essentially I’m supposed to be able to think of ways of how to misuse a pattern in the interview? Which class of programmers can best answer this question? The best ones? The medium ones? I'm not sure.... And these were both bright guys. I read more than enough to get better at my job but had never actually bothered to seek out criticisms of the most simple of the design patterns like this one. Do people think such questions are valid and that I ought to know the objections off by heart? Or that it is reasonable to be able to work out what other people who are missing the point would do on the fly? Or do you think I’m at least partially right that the question is too unsubtle and that the questions ought to be better thought out in order to make sure only good candidates can answer. PS. Please don’t think I’m saying that I’m just so clever that I know everything automatically - I’ve learnt the hard way like everyone else. But avoiding global data is hardly revolutionary.

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  • Do You Really Know Your Programming Languages?

    - by Kristopher Johnson
    I am often amazed at how little some of my colleagues know or care about their craft. Something that constantly frustrates me is that people don't want to learn any more than they need to about the programming languages they use every day. Many programmers seem content to learn some pidgin sub-dialect, and stick with that. If they see a keyword or construct that they aren't familiar with, they'll complain that the code is "tricky." What would you think of a civil engineer who shied away from calculus because it had "all those tricky math symbols?" I'm not suggesting that we all need to become "language lawyers." But if you make your living as a programmer, and claim to be a competent user of language X, then I think at a minimum you should know the following: Do you know the keywords of the language and what they do? What are the valid syntactic forms? How are memory, files, and other operating system resources managed? Where is the official language specification and library reference for the language? The last one is the one that really gets me. Many programmers seem to have no idea that there is a "specification" or "standard" for any particular language. I still talk to people who think that Microsoft invented C++, and that if a program doesn't compile under VC6, it's not a valid C++ program. Programmers these days have it easy when it comes to obtaining specs. Newer languages like C#, Java, Python, Ruby, etc. all have their documentation available for free from the vendors' web sites. Older languages and platforms often have standards controlled by standards bodies that demand payment for specs, but even that shouldn't be a deterrent: the C++ standard is available from ISO for $30 (and why am I the only person I know who has a copy?). Programming is hard enough even when you do know the language. If you don't, I don't see how you have a chance. What do the rest of you think? Am I right, or should we all be content with the typical level of programming language expertise? Update: Several great comments here. Thanks. A couple of people hit on something that I didn't think about: What really irks me is not the lack of knowledge, but the lack of curiosity and willingness to learn. It seems some people don't have any time to hone their craft, but they have plenty of time to write lots of bad code. And I don't expect people to be able to recite a list of keywords or EBNF expressions, but I do expect that when they see some code, they should have some inkling of what it does. Few people have complete knowledge of every dark corner of their language or platform, but everyone should at least know enough that when they see something unfamiliar, they will know how to get whatever additional information they need to understand it.

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  • What to Expect in Rails 4

    - by mikhailov
    Rails 4 is nearly there, we should be ready before it released. Most developers are trying hard to keep their application on the edge. Must see resources: 1) @sikachu talk: What to Expect in Rails 4.0 - YouTube 2) Rails Guides release notes: http://edgeguides.rubyonrails.org/4_0_release_notes.html There is a mix of all major changes down here: ActionMailer changes excerpt: Asynchronously send messages via the Rails Raise an ActionView::MissingTemplate exception when no implicit template could be found ActionPack changes excerpt Added controller-level etag additions that will be part of the action etag computation Add automatic template digests to all CacheHelper#cache calls (originally spiked in the cache_digests plugin) Add Routing Concerns to declare common routes that can be reused inside others resources and routes Added ActionController::Live. Mix it in to your controller and you can stream data to the client live truncate now always returns an escaped HTML-safe string. The option :escape can be used as false to not escape the result Added ActionDispatch::SSL middleware that when included force all the requests to be under HTTPS protocol ActiveModel changes excerpt AM::Validation#validates ability to pass custom exception to :strict option Changed `AM::Serializers::JSON.include_root_in_json' default value to false. Now, AM Serializers and AR objects have the same default behaviour Added ActiveModel::Model, a mixin to make Ruby objects work with AP out of box Trim down Active Model API by removing valid? and errors.full_messages ActiveRecord changes excerpt Use native mysqldump command instead of structure_dump method when dumping the database structure to a sql file. Attribute predicate methods, such as article.title?, will now raise ActiveModel::MissingAttributeError if the attribute being queried for truthiness was not read from the database, instead of just returning false ActiveRecord::SessionStore has been extracted from Active Record as activerecord-session_store gem. Please read the README.md file on the gem for the usage Fix reset_counters when there are multiple belongs_to association with the same foreign key and one of them have a counter cache Raise ArgumentError if list of attributes to change is empty in update_all Add Relation#load. This method explicitly loads the records and then returns self Deprecated most of the 'dynamic finder' methods. All dynamic methods except for find_by_... and find_by_...! are deprecated Added ability to ActiveRecord::Relation#from to accept other ActiveRecord::Relation objects Remove IdentityMap ActiveSupport changes excerpt ERB::Util.html_escape now escapes single quotes ActiveSupport::Callbacks: deprecate monkey patch of object callbacks Replace deprecated memcache-client gem with dalli in ActiveSupport::Cache::MemCacheStore Object#try will now return nil instead of raise a NoMethodError if the receiving object does not implement the method, but you can still get the old behavior by using the new Object#try! Object#try can't call private methods Add ActiveSupport::Deprecations.behavior = :silence to completely ignore Rails runtime deprecations What are the most important changes for you?

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  • Calling cdecl Functions That Have Different Number of Arguments

    - by KlaxSmashing
    I have functions that I wish to call based on some input. Each function has different number of arguments. In other words, if (strcmp(str, "funcA") == 0) funcA(a, b, c); else if (strcmp(str, "funcB") == 0) funcB(d); else if (strcmp(str, "funcC") == 0) funcC(f, g); This is a bit bulky and hard to maintain. Ideally, these are variadic functions (e.g., printf-style) and can use varargs. But they are not. So exploiting the cdecl calling convention, I am stuffing the stack via a struct full of parameters. I'm wondering if there's a better way to do it. Note that this is strictly for in-house (e.g., simple tools, unit tests, etc.) and will not be used for any production code that might be subjected to malicious attacks. Example: #include <stdio.h> typedef struct __params { unsigned char* a; unsigned char* b; unsigned char* c; } params; int funcA(int a, int b) { printf("a = %d, b = %d\n", a, b); return a; } int funcB(int a, int b, const char* c) { printf("a = %d, b = %d, c = %s\n", a, b, c); return b; } int funcC(int* a) { printf("a = %d\n", *a); *a *= 2; return 0; } typedef int (*f)(params); int main(int argc, char**argv) { int val; int tmp; params myParams; f myFuncA = (f)funcA; f myFuncB = (f)funcB; f myFuncC = (f)funcC; myParams.a = (unsigned char*)100; myParams.b = (unsigned char*)200; val = myFuncA(myParams); printf("val = %d\n", val); myParams.c = (unsigned char*)"This is a test"; val = myFuncB(myParams); printf("val = %d\n", val); tmp = 300; myParams.a = (unsigned char*)&tmp; val = myFuncC(myParams); printf("a = %d, val = %d\n", tmp, val); return 0; } Output: gcc -o func func.c ./func a = 100, b = 200 val = 100 a = 100, b = 200, c = This is a test val = 200 a = 300 a = 600, val = 0

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  • Running out of memory.. How?

    - by maxdj
    I'm attempting to write a solver for a particular puzzle. It tries to find a solution by trying every possible move one at a time until it finds a solution. The first version tried to solve it depth-first by continually trying moves until it failed, then backtracking, but this turned out to be too slow. I have rewritten it to be breadth-first using a queue structure, but I'm having problems with memory management. Here are the relevant parts: int main(int argc, char *argv[]) { ... int solved = 0; do { solved = solver(queue); } while (!solved && !pblListIsEmpty(queue)); ... } int solver(PblList *queue) { state_t *state = (state_t *) pblListPoll(queue); if (is_solution(state->pucks)) { print_solution(state); return 1; } state_t *state_cp; puck new_location; for (int p = 0; p < puck_count; p++) { for (dir i = NORTH; i <= WEST; i++) { if (!rules(state->pucks, p, i)) continue; new_location = in_dir(state->pucks, p, i); if (new_location.x != -1) { state_cp = (state_t *) malloc(sizeof(state_t)); state_cp->move.from = state->pucks[p]; state_cp->move.direction = i; state_cp->prev = state; state_cp->pucks = (puck *) malloc (puck_count * sizeof(puck)); memcpy(state_cp->pucks, state->pucks, puck_count * sizeof(puck)); /*CRASH*/ state_cp->pucks[p] = new_location; pblListPush(queue, state_cp); } } } return 0; } When I run it I get the error: ice(90175) malloc: *** mmap(size=2097152) failed (error code=12) *** error: can't allocate region *** set a breakpoint in malloc_error_break to debug Bus error The error happens around iteration 93,000. From what I can tell, the error message is from malloc failing, and the bus error is from the memcpy after it. I have a hard time believing that I'm running out of memory, since each game state is only ~400 bytes. Yet that does seem to be what's happening, seeing as the activity monitor reports that it is using 3.99GB before it crashes. I'm using http://www.mission-base.com/peter/source/ for the queue structure (it's a linked list). Clearly I'm doing something dumb. Any suggestions?

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  • Ruby: Parse, replace, and evaluate a string formula

    - by Swartz
    I'm creating a simple Ruby on Rails survey application for a friend's psychological survey project. So we have surveys, each survey has a bunch of questions, and each question has one of the options participants can choose from. Nothing exciting. One of the interesting aspects is that each answer option has a score value associated with it. And so for each survey a total score needs to be calculated based on these values. Now my idea is instead of hard-coding calculations is to allow user add a formula by which the total survey score will be calculated. Example formulas: "Q1 + Q2 + Q3" "(Q1 + Q2 + Q3) / 3" "(10 - Q1) + Q2 + (Q3 * 2)" So just basic math (with some extra parenthesis for clarity). The idea is to keep the formulas very simple such that anyone with basic math can enter them without resolving to some fancy syntax. My idea is to take any given formula and replace placeholders such as Q1, Q2, etc with the score values based on what the participant chooses. And then eval() the newly formed string. Something like this: f = "(Q1 + Q2 + Q3) / 2" # some crazy formula for this survey values = {:Q1 => 1, :Q2 => 2, :Q3 => 2} # values for substitution result = f.gsub(/(Q\d+)/) {|m| values[$1.to_sym] } # string to be eval()-ed eval(result) So my questions are: Is there a better way to do this? I'm open to any suggestions. How to handle formulas where not all placeholders were successfully replaced (e.g. one question wasn't answered)? Ex: {:Q3 = 2} wasn't in values hash? My idea is to rescue eval()... any thoughts? How to get proper result? Should be 2.5, but due to integer arithmetic, it will truncate to 2. I can't expect people who provide the correct formula (e.g. / 2.0 ) to understand this nuance. I do not expect this, but how to best protect eval() from abuse (e.g. bad formula, manipulated values coming in)? Thank you!

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  • approximating log10[x^k0 + k1]

    - by Yale Zhang
    Greetings. I'm trying to approximate the function Log10[x^k0 + k1], where .21 < k0 < 21, 0 < k1 < ~2000, and x is integer < 2^14. k0 & k1 are constant. For practical purposes, you can assume k0 = 2.12, k1 = 2660. The desired accuracy is 5*10^-4 relative error. This function is virtually identical to Log[x], except near 0, where it differs a lot. I already have came up with a SIMD implementation that is ~1.15x faster than a simple lookup table, but would like to improve it if possible, which I think is very hard due to lack of efficient instructions. My SIMD implementation uses 16bit fixed point arithmetic to evaluate a 3rd degree polynomial (I use least squares fit). The polynomial uses different coefficients for different input ranges. There are 8 ranges, and range i spans (64)2^i to (64)2^(i + 1). The rational behind this is the derivatives of Log[x] drop rapidly with x, meaning a polynomial will fit it more accurately since polynomials are an exact fit for functions that have a derivative of 0 beyond a certain order. SIMD table lookups are done very efficiently with a single _mm_shuffle_epi8(). I use SSE's float to int conversion to get the exponent and significand used for the fixed point approximation. I also software pipelined the loop to get ~1.25x speedup, so further code optimizations are probably unlikely. What I'm asking is if there's a more efficient approximation at a higher level? For example: Can this function be decomposed into functions with a limited domain like log2((2^x) * significand) = x + log2(significand) hence eliminating the need to deal with different ranges (table lookups). The main problem I think is adding the k1 term kills all those nice log properties that we know and love, making it not possible. Or is it? Iterative method? don't think so because the Newton method for log[x] is already a complicated expression Exploiting locality of neighboring pixels? - if the range of the 8 inputs fall in the same approximation range, then I can look up a single coefficient, instead of looking up separate coefficients for each element. Thus, I can use this as a fast common case, and use a slower, general code path when it isn't. But for my data, the range needs to be ~2000 before this property hold 70% of the time, which doesn't seem to make this method competitive. Please, give me some opinion, especially if you're an applied mathematician, even if you say it can't be done. Thanks.

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